Fluorinated epoxyketone-based compounds and uses thereof as proteasome inhibitors

ABSTRACT

The present application relates to novel fluorinated epoxyketone-based compounds, compositions comprising these compounds and their use, in particular for the treatment of diseases, disorders or conditions mediated by proteasome inhibition. In particular, the present application includes compounds of Formula I, and compositions and uses thereof:

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of co-pending U.S. patentapplication Ser. No. 14/420,817 filed on Feb. 10, 2015 which is aNational Stage Application of International Application No.PCT/CA2013/050620 filed on Aug. 13, 2013 which claims the benefit ofpriority from U.S. Provisional Patent Application Ser. No. 61/682,836filed on Aug. 14, 2012, the contents of each of which are incorporatedherein by reference in their entirely.

FIELD

The present application relates to novel fluorinated epoxyketone-basedcompounds, to processes for their preparation, to compositionscomprising them, and to their use in therapy. More particularly, itrelates to compounds useful in the treatment of diseases, disorders orconditions mediated by or associated with proteasome inhibition.

BACKGROUND

The multi-catalytic proteasome is the ubiquitous proteinase found incells throughout the plant and animal kingdoms that is responsible forthe ubiquitin-dependent degradation of intracellular proteins. Thousandsof copies are found in all cells, in both the cytoplasm and the nucleus,which constitute up to 3% of all cellular protein content. Proteasomesserve multiple intracellular functions, including the degradation ofdamaged proteins and the modulation of many regulatory proteins thataffect inflammatory processes, viral shedding, the cell cycle, growth,and differentiation, to name but a few [Cell 1994, 79, 13-21; Nat. Rev.Mol. Cell Biol. 2005, 6, 79-87; Semin. Oncol. 2004, 31, 3-9; Chem. Biol.2001, 8, 739-758].

The ubiquitin-proteasome pathway (UPP), also known as theubiquitin-proteasome system (UPS), regulates the degradation ofintracellular proteins with specificity as to target, time and space.The pathway plays a central role in recognizing and degrading misfoldedand abnormal proteins in most mammalian cells [Nature 2000, 404,770-774]. Such a process is very important in maintaining the biologicalhomeostasis and regulation of different cellular processes such as butnot limited to cell differentiation, cell cycle control, antigenprocessing and hormone metabolism [EMBO J. 1998, 17, 7151-7160; Chem.Biol. 2001, 8, 739-758]. In this pathway, the 26S proteasome is the mainproteolytic component, which is found in all eukaryotic cells and ismade up of of the cylinder-shaped multi-catalytic proteinase complex(MPC) 20S proteasome and two regulatory particle (RP) 19S proteasomes.The 19S proteasome located at each end of the 20S proteasome is made upof 18 subunits, and controls the recognition, unfolding, andtranslocation of protein substrates into the lumen of the 20S proteasome[Annu. Rev. Biochem. 1999, 68, 1015-1068].

X-ray crystallography of the 26S proteasome revealed that the 20Sproteasome is composed of 28 protein subunits arranged in four stackrings, with each ring made up of seven α- and β-type subunits, followingan α1-7β1-7 stoichiometry [Science 1995, 268, 533-539; Nature (London)1997, 386, 463-467]. The two outer chambers are formed by a subunits,while the central chamber, containing the proteolytic active sites, ismade up of 1 subunits. Three of the 14 β subunits are responsible forthe post-glutamyl peptide hydrolysis activity (PGPH, attributed to β1),trypsin-like activity (T-L, β2), and chymotripsin-like activity (CT-L,β5), respectively, and all these three active subunits hydrolyze theamide bond of protein substrates with the hydrophilic γ-hydroxyl groupof the N-terminal threonine (Oγ-Thr1).

Rising interest in the mechanism and function of the proteasomes and theubiquitin system revealed that it is hard to find any aspect of thecellular metabolic network that is not directly or indirectly affectedby the degradation system. This includes, for example the cell cycle,the “quality control” of newly synthesized proteins (ERAD: EndoplasmicReticulum Associated Protein Degradation), transcription factorregulation, gene expression, cell differentiation and immune response aswell as pathologic processes such as cancer, neurodegenerative diseases,lipofuscin formation, diabetes, atherosclerosis, inflammatory processesand cataract formation in addition to the aging process and thedegradation of oxidized proteins in order to maintain cell homeostasis.But this seems to be only a small aspect of the general view. Thevarious regulator proteins that are able to change the rate orspecificity of proteolysis, fitting it out for highly specialized tasks,or the precise regulation of the half-life of cellular proteins byubiquitin-mediated degradation shape the proteasome and theubiquitin-proteasome system into a useful part of cellular function inthe three kingdoms of bacteria, plants and animals.

Cancer is a leading cause of death worldwide. Despite significantefforts to find new approaches for treating cancer, the primarytreatment options remain surgery, chemotherapy and radiation therapy,either alone or in combination. Surgery and radiation therapy, however,are generally useful only for fairly defined types of cancer, and are oflimited use for treating patients with disseminated disease.Chemotherapy is a method that is useful in treating patients withmetastatic cancers or diffuse cancers such as leukemias. However,although chemotherapy can provide a therapeutic benefit, it often failsto result in cure of the disease due to the patient's cancer cellsbecoming resistant to the chemotherapeutic agent. Therefore, a needexists for additional chemotherapeutics to treat cancer.

The concept of proteasome inhibition as a therapeutic approach in canceris known. The first-in-class inhibitor bortezomib is a potent,selective, and reversible proteasome inhibitor which targets the 26Sproteasome complex and inhibits its function. Proteasomal degradation ofmisfolded or damaged proteins proceeds by recognition ofpoly-ubiquitinated proteins by the 19S regulatory subunit of the 26Sprotease, and subsequent hydrolysis to small polypeptides.

The successful development of bortezomib for treatment ofrelapsed/refractory multiple myeloma (MM) and mantle cell lymphoma, hasshown proteasome inhibition to be a useful therapeutic strategy [Nat.Rev. Cancer 2004, 4, 349-360; Bioorg. Med. Chem. Lett. 1998, 8, 333-338;J. Clin. Oncol. 2002, 20, 4420-4427; N. Engl. J. Med. 2003, 348,2609-2617; N. Engl. J. Med. 2005, 352, 2487-2498; J. Clin. Oncol. 2007,25, 3892-3901]. Bortezomib primarily inhibits chymotryptic, withoutaltering tryptic or caspase-like, proteasome activity. Bortezomib haspleiotropic effects on multiple myeloma biology by targeting a)cell-cycle regulatory proteins; b) the unfolded protein response (UPR)pathway via modulating the transcriptional activity of plasma celldifferentiation factor X-box binding protein-I (XBP-I); c) p53-mediatedapoptosis/MDM2; d) DNA repair mechanisms; and e) classicalstress-response pathways via both intrinsic (caspase-9 mediated) andextrinsic (caspase-3 mediated) cell death cascades. Specifically,bortezomib activates c-Jun N-terminal kinase (JNK), which triggersmitochondrial apoptotic signalling: release of cytochrome-c (cyto-c) andsecond mitochondrial activator of caspases (Smac) from mitochondria tocytosol, followed by activation of caspase-9 and caspase-3.

Although bortezomib has shown clinical success, a significant fractionof patients relapse or are refractory to treatment [J. Clin. Oncol.2005, 23, 676-684; J. Clin. Oncol. 2005, 23, 667-675]. Additionally,dose-limiting toxicities (DLT), including a painful peripheralneuropathy and thrombocytopenia, have been reported [J. Clin. Oncol.2006, 24, 3113-3120; Blood 2005, 106, 3777-3784]. To date, it is unclearwhether these toxicities can be attributed to off-target effects becausebortezomib inhibits other enzymes such as serine proteases.

A recently reported structural analogue of the microbial natural productepoxomicin, known as carfilzomib (also called PR-171) was initiallyidentified for its antitumor activity and subsequently shown to be apotent inhibitor of the proteasome [Cancer Res. 2007, 67, 6383-6391;Curr. Opin. Drug Discovery 2008, 11, 616-625; J. Am. Chem. Soc. 2000,122, 1237-1238; J. Antibiot. (Tokyo) 1992, 45, 1746-1752; Bioorg. Med.Chem. Lett. 1999, 9, 2283-2288; Cancer Res. 1999, 59, 2798-2801; Proc.Natl. Acad. Sci. U.S.A. 1999, 96, 10403-10408]. Carfilzomib selectivelyinhibits the CT-L activity of the 20S proteasome with minimal crossreactivity to other protease classes.

Preclinical studies and phase I clinical studies demonstrated thatconsecutive daily dosing schedules with carfilzomib are bothwell-tolerated and promote antitumor activity in hematologicmalignancies, including patients previously treated with bortezomib[Blood 2007, 110, 3281-3290; Br. J. Hamaetol. 2007, 136, 814-828; Blood2007, 110, 409; Blood 2007, 110, 411]. Carfilzomib is currently beingevaluated in phase I and phase II clinical trials in multiple myeloma,non-Hodgkin's lymphoma, and solid tumors.

Clinical responses to known proteasome inhibitor therapies requirefrequent dosing (e.g., twice per week) and prolonged treatment. Forexample, both bortezomib and carfilzomib are administered intravenously(iv) on biweekly or more frequent dosing schedules with a treatment thatcan extend for over 6 months. Therefore, the development of orallybioavailable proteasome inhibitors that would allow for dosingflexibility and improve patient convenience is desirable.

Proteasome inhibitor-based therapeutics are useful in other diseasesbeyond clinical oncology. In addition to its role in cancer therapy, theproteasome is linked to the production of the majority of the class Iantigens [Nature 1992, 357, 375-379]. Therefore excessive inhibition ofthe proteasome might increase the chance of viral infections. Forexample, it was reported that replication of the HIV-1 virus could belimited by the degradative actions of the proteasome and that theproteasome inhibitor, MG-132 or lactacystin, enhanced the ability of thevirus to replicate [J. Virol. 1998, 72, 3845-3850]. In contrast, anumber of recent publications have suggested that theubiquitin-proteasome pathway has a useful role in the processing ofretroviral assembly, maturation, and budding [Proc. Natl. Acad. Soc. USA2000, 97, 13069-13074; Proc. Natl. Acad. Sci. USA 2000, 97, 13057-13062;Proc. Natl. Acad. Sci. USA 2000, 97, 13063-13068]. Proteasome inhibitionalso interferes with gag polyprotein processing, release, and maturationof HIV-1 and HIV-2, and ubiquitination is required for retroviralrelease. Hence, proteasome inhibitors can be useful for the treatment ofHIV and other viral infections.

Proteasome inhibition also has clinical potential for treatment ofinflammatory and autoimmune diseases through multiple pathways,including MHC-mediated antigen presentation, cytokine and cell cycleregulation, and apoptosis [J. Rheumatol. 2005, 32, 1192-119]. Ininflammatory arthritis, it was shown that NF-κB regulates multiplecritical cytokines involved in the pathogenesis of rheumatoid arthritis(RA) [Arthritis Rheum. 2004, 50, 2381-2386; Arthritis Rheum. 2004, 50,3541-3548]. In the peptoglycan/polysaccharide-induced inflammatoryarthritis model, a proteasome inhibitor improved the arthritis score bysuppressing the activation of NF-κB, reducing the expression of celladhesion molecules and IL-6. In addition, proteasome inhibition mayregulate the development of inflammatory arthritis by controllingangiogenesis [J. Mol. Med. 2003, 81, 235-245].

Psoriasis is one of the prototypical T cell-mediated diseases, and itsdevelopment is related to the activation of NF-κB. Administration of aproteasome inhibitor has been reported to reduce the size of psoriaticlesions in human skin explants grafted onto mice. The treatment alsoresulted in reduced super antigen-mediated T-cell activation, attenuatedcell adhesion molecule expression and decreased expression of T-cellactivation markers that were significantly elevated during the diseaseprocess [J. Clin. Invest. 2002, 109, 671-679].

In addition, other studies showed oral proteasome inhibition bybortezomib significantly limited overall inflammation, reduced theactivation of NF-κB, lowered cell adhesion molecule expression,inhibited nitric oxide synthase activity, attenuated the circulatinglevels of IL-6, reduced the arthritic index and swelling observed in thejoints of the animals, and improved the histologic appearance of thejoints compared with vehicle-treated animals [Carcinogenesis 2000, 2,505-515].

A link between proteasome inhibition, allergy and asthma has also beenshown. Abnormal activation of type 2 helper T cells (Th2) results inasthmatic and allergic symptoms [Nat. Immunol. 2002, 3, 715-720]. E3ubiquitin ligase Itch plays a useful role in maintaining immunetolerance mediated through Th2 cells both in vitro and in vivo. Itchdeficient mice failed to block the development of airway inflammation inan allergic model [J. Clin. Invest. 2006, 116, 1117-1126]. Consistentwith these findings, useful therapeutic effects were observed in arodent model of allergen-induced asthma [J. Allergy Clin. Immunol. 1999,104, 294-300].

Other inflammatory and autoimmune diseases have been linked to theubiquitin-proteasome system (UPS), such as seronegativespondyloarthropathies (SpA) which are a group of diseases characterizedby, but not limited to, axial joint inflammation. Ankylosing spondylitis(AS) is the prototypical SpA. Most patients with AS carry the MHC classI HLA-B27 gene, and therefore much research effort has been directed atunderstanding the role of this gene in the disease pathogenesis. Therehas also been interest focused on determining the origin and nature ofthe peptides being presented by HLA-B27 and the cell surface expressionof misfolded HLA-B27, two areas in which the UPS is known to play arole.

The UPS is involved in the regulation or induction of apoptosis.Apoptosis has been implicated in both experimental models and clinicalsystemic lupus erythematosus (SLE). In mature, activated lymphocytes,the proteasome inhibitor lactacystin induces DNA fragmentation andapoptosis in a dose-dependent fashion, indicating that proteasomesuppresses apoptosis in these cells. Altered clearance of auto antigensis thought to allow for targeting by the immune system and thedevelopment of autoimmunity. The involvement of UPS in regulating thelevels of Ku70 and other autoantigens has been reported [J. Biol. Chem.1998, 273, 31068-31074; J. Cell. Sci. 1994, 107 (Pt 11), 3223-3233; Exp.Cell. Res. 2006, 312, 488-499].

Proteasome inhibition has also been linked to heart disease. Evidencecontinues to emerge to support a hypothesis that proteasome functionalinsufficiency represents a common pathological phenomenon in a largesubset of heart disease, compromises protein quality control in heartmuscle cells, and thereby acts as a major pathogenic factor promotingthe progression of the subset of heart disease to congestive heartfailure. This front is represented by the studies on the UPS in cardiacproteinopathy, which have taken advantage of a transgenic mouse modelexpressing a fluorescence reporter for UPS proteolytic function.

In addition, pharmacological inhibition of the proteasome has beenexplored experimentally as a potential therapeutic strategy to interveneon some forms of heart disease, such as pressure-overload cardiachypertrophy, viral myocarditis, and myocardial ischemic injury[Biochimica et Biophysica Acta—Gene Regulatory Mechanisms, 1799(9),2010, 597-668]. Furthermore, initial reports on the effects ofproteasome inhibitors in cardiovascular diseases, indicate thatproteasome inhibition might be a useful therapeutic strategy for thereduction of the proliferative phenomena of the progression stage ofatherogenesis [Cardiovasc. Res. 2004, 61, 11-21]. Recent data on theimprovement of endothelium-dependent vasorelaxation in vitro,correlating with an increase in endothelial nitric oxide synthase (eNOS)expression, suggest a therapeutic potential of proteasome inhibition inthe early stages of atherosclerosis [FASEB 2004, 18, 272-279].

Proteasome inhibitors have been shown to exert a substantialanti-inflammatory effect, which was attributed to a reduction in theactivity of the factor NF-κB [Cardiovasc. Res. 2004, 61, 11-21]. As thepathogenesis of cardiovascular events in diabetic patients involvesinflammation, the use of proteasome inhibitors may be a useful therapy.In addition to epidemiological evidence for the role of inflammation indiabetes-associated cardiovascular events, clinical studies of patientson cardio-protective drug regimens have revealed that many of thepharmacotherapies mediate their benefits, at least in part, throughanti-inflammatory activities. This is the case for one class of drugsthat improves adipose tissue physiology and insulin sensitivity, theperoxisome proliferator-activated receptor-γ (PPARγ) agonists[Arterioscler. Thromb. Vasc. Biol. 2002, 22, 717-726]. For example, thePPARγ agonist rosiglitazone, reducing inflammation, may prevent plaqueprogression to an unstable phenotype in diabetic patients withasymptomatic carotid stenosis, enlisted to undergo carotidendarterectomy for extracranial high-grade (>70%) internal carotidartery stenosis [Diabetes 2006, 55, 622-632].

The anti-inflammatory effects of glitazones are felt to be mediatedpartly by their beneficial effects on glycemia, but there is alsoevidence that glitazones may directly modulate inflammation viatranscription factors such as NF-κB [Arterioscler. Thromb. Vasc. Biol.2002, 22, 717-726]. In line with this, recent data have shown aninhibitory effect of rosiglitazone on ubiquitin-proteasome activity indiabetic lesions [Diabetes 2006, 55, 622-632]. At the same level ofblood glucose levels, diabetic patients treated with rosiglitazone hadthe lowest level of ubiquitin and proteasome 20S activity, plaqueinflammatory cells, cytokines, oxidative stress and MMP-9 associatedwith the highest content of plaque interstitial collagen. Patientsassigned to rosiglitazone had lesser plaque progression to an unstablephenotype compared with patients assigned to placebo.

For aspirin and statins, two of the most successful drugs in treatmentof cardiovascular diseases, a proteasome inhibitory effect has beendescribed [Mol. Pharmacol. 2002, 62, 1515-1521].

Drugs that modulate the proteasomal degradation of proteins could beuseful agents for the treatment of insulin-resistant and type-2diabetes, and pharmacological therapies targeting UPS activity may beuseful in the treatment of vascular biology disorders associated withdiabetes [Cardiovascular Diabetology 2007, 6:35, 1-9].

The ubiquitin-proteasome system is also believed to degrade the majorcontractile skeletal muscle proteins and plays a major role in musclewasting. Different and multiple events in the ubiquitination,deubiquitination and proteolytic machineries are responsible for theactivation of the system and subsequent muscle wasting. However, otherproteolytic enzymes act upstream (possibly m-calpain, cathepsin L,and/or caspase-3) and downstream (tri-peptidyl-peptidase II andamino-peptidases) of the UPS, for the complete breakdown of themyofibrillar proteins into free amino acids. Recent studies haveidentified a few proteins that seem necessary for muscle wasting i.e.the MAFbx (muscle atrophy F-box protein, also called atrogin-1) andMuRF-1 (muscle-specific RING ubiquitin-protein ligases) proteins. Thecharacterization of their signaling pathways is leading to newpharmacological approaches that can be useful to block or partiallyprevent muscle wasting in human patients [Essays Biochem. 2005, 41,173-86].

The UPS has also been linked to the development of human obesity. Forexample, it was shown that there is a possible correlation betweenplasma ubiquitin, 26S proteasome levels, and obesity. The body massindex (BMI), plasma ubiquitin levels, and 26S proteasome activity levelswere determined and statistically analyzed. Comparison of theimmunoglobulin among the underweight, normal weight, and overweightgroups demonstrated that plasma ubiquitin is significantly decreased inobese individuals versus normal controls, and plasma ubiquitin levelswere found to be inversely correlated with the BMI. In addition, therewas an inverse relationship between 20S proteasome levels in red bloodcells and BMI, whereas 26S proteasome activity was found to be dependentquantitatively to S5a in erythrocytes. Furthermore, immunoglobulin issignificantly decreased in overweight individuals versus normal controls[Metabolism 2009, 58(11), 1643-8].

A wide variety of preclinical and early clinical studies have beenperformed to test the potential usefulness of proteasome inhibitors forthe treatment of neurodegenerative disorders, including Alzheimer's (AD)and Parkinson's (PD) diseases. These CNS disorders are characterized bya selective loss of neurons in specific, but different, regions of thebrain, and the result is often a disruption to motor, sensory orcognitive systems, resulting in severe disability of the patient. Thepathological characteristic of many neurodegenerative diseases is thepresence of distinctive ubiquitin-positive, intra- or extracellularinclusion bodies in affected regions of the brain. In general, theseinclusions are made up of insoluble, unfolded, ubiquitylatedpolypeptides that fail to be targeted and degraded by the 26S proteasome[J. Pathol. 1988, 155, 9-15; Neuron 2001, 29, 15-32]. Their apparentstability may, in part, be due to decreased levels of 26S proteasomalactivity that is associated with increasing age [Ann. N. Y. Acad. Sci.2001, 928, 54-64].

Proteins associated with the UPS are now known to play either a director indirect role in familial forms of neurodegenerative disease and, inparticular, PD. UPS-mediated post-translational modification anddegradation of proteins is useful for most cellular processes such ascell cycling, DNA repair, cell signaling, gene transcription andapoptosis. Historically, it was recognized that the UPS is the majorroute by which proteins are selected for temporal and spatialdegradation in eukaryotic organisms [Cell 2004, 116, 181-190; Nat. Rev.Mol. Cell Biol. 2003, 4, 192-201]. The key constituents of theinclusions associated with neurodegenerative disorders are mis-foldedproteins. The major causes of protein mis-folding and subsequent loss offunction are mis-sense mutations, modifications or posttranslationaldamage of proteins, or expansion of amino acid repeats as is observed inpolyglutamine (polyQ) disorders such as Huntington's disease (HD).

Of all the neurodegenerative diseases, PD is most closely associatedwith aberrant protein processing via the UPS. Indeed, of the knownproteins associated with hereditary forms of PD, Parkin and UCH-L1 arecomponents of the UPS, whereas modified and/or mutant α-Synuclein andDJ-1 are degraded by the system [Nature 1998, 392, 605-608; Nature 1998,395, 451-452; J. Biol. Chem. 2003, 278, 36588-36595].

A wide variety of preclinical and early clinical studies have beenperformed to test the potential usefulness of proteasome inhibitors forthe treatment of Alzheimer's disease [J. Neurochem. 1999, 72, 255-261],amyotrophic lateral sclerosis [J. Neurol. Sci. 1996, 139, 15-20],autoimmune thyroid disease [Tissue Antigens. 1997, 50, 153-163],cachexia [N. Engl. J. Med. 1996, 335, 1897-1905; Am. J. Physiol. 1999,277, 332-341], Crohn's disease [J. Pharmacol. Exp. Ther. 1997, 282,1615-1622], Hepatitis B [Oncogene, 1998, 16, 2051-2063], inflammatorybowel disease [Inflamm. Bowel Dis. 1996, 2, 133-147], sepsis [Ann. Surg.1997, 225, 307-316], systemic lupus erythematosus [J. Exp. Med. 1996,10, 1313-1318], and transplantation rejection and related immunology[Drug Discov. Today 1999, 4, 63-70; Transplantation 2001, 72, 196-202].

The ubiquitin-proteasome system is also believed to play roles in thepathogenesis of eye diseases. Accumulation of the cytotoxic abnormalproteins in eye tissues is etiologically associated with manyage-related eye diseases such as retina degeneration, cataract, andcertain types of glaucoma. Age- or stress-induced impairment oroverburdening of the UPP appears to contribute to the accumulation ofabnormal proteins in eye tissues. Cell cycle and signal transduction areregulated by the conditional UPP-dependent degradation of the regulatorsof these processes. Impairment or overburdening of the UPP could alsoresult in dysregulation of cell cycle control and signal transduction.The consequences of the improper cell cycle and signal transductioninclude defects in ocular development, wound healing, angiogenesis, orinflammatory responses. Methods that enhance or preserve UPP function orreduce its burden may be useful strategies for preventing age-relatedeye diseases [Pro. Mol. Biol. & Trans. Sc., Vol. 109, 2012, 347-396].

The search for subunit selective inhibitors is predominantly conductedby either screening of natural products [Bioorg. Med. Chem. Lett. 1999,9, 3335-3340], rational design [Chem. Biol. 2009, 16, 1278-1289], orcompound library building [Proc. Natl. Acad. Sci. USA 2001, 98,2967-2972; Org. Biomol. Chem. 2007, 5, 1416-1426]. It was noted that inthese studies the effect of fluorine functionality in proteasomeinhibitors is relatively uncharted [Bioorg. Med. Chem. Lett. 2009, 19,83-86].

The epoxomicin analog PR-047 was recently reported to be anorally-bioavailable candidate that displayed moderate to poor metabolicproperties [J. Med. Chem. 2009, 52, 3028-3038]. While not wishing to belimited by theory, this poor metabolic property is thought to be due tothe methoxy groups in the serine (OMe) side-chains undergoingdemethylation to the O-desmethyl metabolite. A need therefore exists tofind a route to block this demethylation pathway to give compoundshaving useful clinical profile.

SUMMARY

A novel class of halogenated epoxyketone-based proteasome inhibitors ofFormula I has been prepared and found to be useful in the treatment ofcancers and other proteasome mediated or associateddisorders.

Accordingly, the present application includes a compound of Formula I ora pharmaceutically acceptable salt, solvate or prodrug thereof:

wherein:

R¹ is selected from the group consisting of C₁₋₁₀alkyl, C₂₋₁₀alkenyl,C₂₋₁₀alkynyl, C₁₋₁₀haloalkyl, C₁₋₁₀cyanoalkyl, C₁₋₁₀alkoxy,C₂₋₁₀alkenyloxy, C₂₋₁₀alkynyloxy, C₃₋₁₀cycloalkyl, heterocycloalkyl,aryl, heteroaryl, C₁₋₆alkylene-O—C₁₋₆alkyl,C₁₋₆alkylene-O—C₁₋₆haloalkyl, C₂₋₆alkenylene-O—C₁₋₆haloalkyl,C₂₋₆alkynylene-O—C₁₋₆haloalkyl, C₁₋₆alkylene-C₃₋₈cycloalkyl,C₁₋₆alkylene-heterocycloalkyl, C₁₋₆alkylene-aryl,C₁₋₆alkylene-heteroaryl, C(O)R⁷, OC(O)R⁷, C(O)OR⁷, C₁₋₆alkylene-O—R⁷,C₁₋₆alkylene-C(O)R⁷, C₁₋₆alkylene-O—C(O)R⁷, C₁₋₆alkylene-C(O)OR⁷,C₁₋₆alkylene-O—C(O)OR⁷, C₁₋₆alkylene-NR⁷R⁸, C₁₋₆alkylene-C(O)NR⁷R⁸,C₁₋₆alkylene-NR⁷C(O)R⁸, C₁₋₆alkylene-NR⁷C(O)NR⁷R⁸, C₁₋₆alkylene-S—R⁷,C₁₋₆alkylene-S(O)R⁷, C₁₋₆alkylene-SO₂R⁷, C₁₋₆alkylene-SO₂NR⁷R⁸,C₁₋₆alkylene-NR⁷SO₂R⁸, C₁₋₆alkylene-NR⁷SO₂NR⁷R⁸, C(O)NR⁷R⁸ andC₁₋₆alkylene-NR⁷C(O)OR⁸, wherein any cyclic moiety is optionallysubstituted with C₁₋₄alkyl and/or is optionally fused to a furthercyclic moiety;

X is absent or is selected from the group consisting of O, NH,NC₁₋₆alkyl, S, S(O), SO₂, C(O), C₁₋₆alkylene, C₂₋₆alkenylene,C₂₋₆alkynylene, C₁₋₆haloalkylene, C₃₋₈cycloalkylene,heterocycloalkylene, arylene and heteroarylene, or X is a combination oftwo or three of O, NH, NC₁₋₆alkyl, S, S(O), SO₂, C₁₋₆alkylene,C₂₋₆alkenylene, C₂₋₆alkynylene, C₁₋₆haloalkylene, C₃₋₈cycloalkylene,heterocycloalkylene, arylene or heteroarylene, bonded together in alinear fashion, provided that two or three of O, NH, NC₁₋₆alkyl, S, S(O)and SO₂ and not bonded directly to each other;

R², R³ and R⁴ are each independently selected from the group consistingof C₁₋₁₀alkyl, C₂₋₁₀alkenyl, C₂₋₁₀alkynyl, C₁₋₁₀haloalkyl,C₁₋₁₀cyanoalkyl, C₁₋₁₀alkoxy, C₂₋₁₀alkenyloxy, C₂₋₁₀alkynyloxy,C₃₋₁₀cycloalkyl, heterocycloalkyl, aryl, heteroaryl,C₁₋₆alkylene-O—C₁₋₆alkyl, C₁₋₆alkylene-O—C₁₋₆haloalkyl,C₂₋₆alkenylene-O—C₁₋₆haloalkyl, C₂₋₆alkynylene-O—C₁₋₆haloalkyl,C₁₋₆alkylene-C₃₋₈cycloalkyl, C₁₋₆alkylene-heterocycloalkyl,C₁₋₆alkylene-aryl, C₁₋₆alkylene-heteroaryl, C(O)R⁷, OC(O)R⁷, C(O)OR⁷,C₁₋₆alkylene-O—R⁷, C₁₋₆alkylene-C(O)R⁷, C₁₋₆alkylene-O—C(O)R⁷,C₁₋₆alkylene-C(O)OR⁷, C₁₋₆alkylene-O—C(O)OR⁷, C₁₋₆alkylene-NR⁷R⁸,C₁₋₆alkylene-C(O)NR⁷R⁸, C₁₋₆alkylene-NR⁷C(O)R⁸,C₁₋₆alkylene-NR⁷C(O)NR⁷R⁸, C₁₋₆alkylene-S—R⁷, C₁₋₆alkylene-S(O)R⁷,C₁₋₆alkylene-SO₂R⁷, C₁₋₆alkylene-SO₂NR⁷R⁸, C₁₋₆alkylene-NR⁷SO₂R⁸,C₁₋₆alkylene-NR⁷SO₂NR⁷R⁸, C(O)NR⁷R⁸ and C₁₋₆alkylene-NR⁷C(O)OR⁸, whereinany cyclic moiety is optionally fused to a further 5- to 7-memberedcyclic moiety, wherein at least one of R², R³ and R⁴ isC₁₋₆-alkylene-O—C₁₋₆haloalkyl, and wherein R², R³ and R⁴ are optionallysubstituted with one or more independently-selected R⁶ groups;

R⁵ is selected from the group consisting of H, C₁₋₆alkyl, C₁₋₆haloalkyl,C₂₋₆alkenyl, C₂₋₆alkynyl, C₃₋₈cycloalkyl, C₁₋₆alkylene-C₃₋₈cycloalkyl,aryl, heteroaryl, and heterocycloalkyl;

R⁶ is selected from the group consisting of C₁₋₆alkyl, OH, halo,O—(C₂₋₃alkylene)-O, C₁₋₆alkoxy, aryloxy, —NH—C₁₋₆alkyl, —N(C₁₋₆alkyl)₂,C₁₋₆alkylene-N(C₁₋₆alkyl)₂, C₁₋₆alkylene-NH—C₁₋₆alkyl, cycloalkyl,heterocycloalkyl, aryl and heteroaryl; and

R⁷ and R⁸ are each independently selected from the group consisting ofH, C₁₋₆alkyl, C₁₋₆haloalkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₃₋₁₀cycloalkyl,C₁₋₆alkylene-C₃₋₁₀cycloalkyl, heterocycloalkyl, aryl, C₁₋₆alkylene-aryl,C₁₋₆alkylene-heterocycloalkyl, heteroaryl, and C₁₋₆alkylene-heteroaryl,wherein any cyclic moiety is optionally fused to a further cyclicmoiety.

The present application also includes a composition comprising one ormore compounds of the application and a carrier. In an embodiment, thecomposition is a pharmaceutical composition comprising one or morecompounds of the application and a pharmaceutically acceptable carrier.

The compounds of the application have been shown to inhibitors ofproteasome activity. Therefore the compounds of the application areuseful for treating diseases, disorders or conditions mediated by orassociated with proteasome inhibition. Accordingly, the presentapplication also includes a method of treating a disease, disorder orcondition mediated by proteasome inhibition, comprising administering atherapeutically effective amount of one or more compounds of theapplication to a subject in need thereof.

In a further embodiment, the compounds of the application are used asmedicaments. Accordingly, the application also includes a compound ofthe application for use as a medicament.

The present application also includes a use of one or more compounds ofthe application for treatment of a disease, disorder or conditionmediated by proteasome inhibition as well as a use of one or morecompounds of the application for the preparation of a medicament fortreatment of a disease, disorder or condition mediated by proteasomeinhibition. The application further includes one or more compounds ofthe application for use in treating a disease, disorder or conditionmediated by proteasome inhibition.

In an embodiment, the disease, disorder or condition mediated byproteasome inhibition is a neoplastic disorder. In an embodiment, thetreatment is in an amount effective to ameliorate at least one symptomof the neoplastic disorder, for example, reduced cell proliferation orreduced tumor mass in a subject in need of such treatment.

In an embodiment, the disease, disorder or condition mediated byproteasome inhibition is cancer.

In an embodiment, the disease, disorder or condition mediated byproteasome inhibition is a disease, disorder or condition associatedwith an uncontrolled and/or abnormal cellular activity affected directlyor indirectly by proteasome inhibition. In another embodiment, theuncontrolled and/or abnormal cellular activity that is affected directlyor indirectly by proteasome inhibition is proliferative activity in acell.

The application also includes a method of inhibiting proliferativeactivity in a cell, comprising administering an effective amount of oneor more compounds of the application to the cell.

In a further embodiment the disease, disorder or condition mediated byproteasome inhibition is cancer and the one or more compounds of theapplication are administered in combination with one or more additionalcancer treatments. In another embodiment, the additional cancertreatment is selected from radiotherapy, chemotherapy, targetedtherapies such as antibody therapies and small molecule therapies suchas tyrosine-kinase inhibitors, immunotherapy, hormonal therapy andanti-angiogenic therapies.

In another embodiment, the disease, disorder or condition mediated byproteasome inhibition is selected from by proteasome inhibition isselected from a viral infection, an inflammatory disease, an autoimmunedisease, heart disease, an age-related eye disease and aneurodegenerative disease.

The application additionally provides a process for the preparation ofcompounds of Formula I. General and specific processes are discussed inmore detail and set forth in the Examples below.

In an embodiment of the present application, the compounds of Formula Icomprise at least one fluorine atom. Factors to be considered whensynthesising fluorine-containing compounds include (a) the relativelysmall size of the fluorine atom (van der Waals radius of 1.47 Å),comparable to hydrogen (van der Waals radius of 1.20 Å), (b) the highlyelectron-withdrawing nature of fluorine, (c) the greater stability ofthe C—F bond compared to the C—H bond and (d) the greater lipophilicityof fluorine compared to hydrogen. The introduction of a fluorine atominto a molecule can alter the physicochemical properties of the compounddue to its electronegativity.

The introduction of a halogen atom into a molecule also provides theopportunity for the use of the molecule in radiolabeling applications.For example, ¹⁸F is used as a radiolabel tracer in the sensitivetechnique of Positron Emission Tomography (PET). Accordingly the presentapplication also includes methods of using the compounds of Formula Ifor diagnostic and imaging purposes.

Other features and advantages of the present application will becomeapparent from the following detailed description. It should beunderstood, however, that the detailed description and the specificexamples while indicating embodiments of the application are given byway of illustration only, since various changes and modifications withinthe spirit and scope of the application will become apparent to thoseskilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present application will now be described in greater detail withreference to the drawings, in which:

FIG. 1 shows the effect of a representative compound of the application(the compound of Example 1) on the enzymatic activity of purifiedproteasomes, compared to bortezomib. Purified beta proteasome subunitsfrom the archaebacteria Thermoplasma acidophilum (A) or whole celllysates from the human myeloma cell line LP1 (B).

FIG. 2 shows the compound of Example 1 synergized with standardantimyeloma therapeutics when combined in a fixed ratio for 72 hours atlow fractional effect levels. Synergy was assessed using the MTS assayand combination index (CI) analysis, where a CI<1 indicates synergybetween two drugs, a CI=1 indicates additivity, and a CI>1 indicatesantagonism.

FIG. 3 shows the effects of the compound of Example 1 on the cellviability of samples from patients with multiple myeloma (A,C) or fromthe peripheral blood of a patient with plasma cell leukemia (B).

DETAILED DESCRIPTION I. Definitions

Unless otherwise indicated, the definitions and embodiments described inthis and other sections are intended to be applicable to all embodimentsand aspects of the application herein described for which they aresuitable as would be understood by a person skilled in the art. Unlessotherwise specified within this application or unless a person skilledin the art would understand otherwise, the nomenclature used in thisapplication generally follows the examples and rules stated in“Nomenclature of Organic Chemistry” (Pergamon Press, 1979), Sections A,B, C, D, E, F, and H. Optionally, a name of a compound may be generatedusing a chemical naming program: ACD/ChemSketch, Version 5.09/September2001, Advanced Chemistry Development, Inc., Toronto, Canada.

The term “compound of the application” or “compound of the presentapplication” and the like as used herein refers to a compound of FormulaI, or a pharmaceutically acceptable salt, solvate and/or prodrugthereof.

As used in the present application, the singular forms “a”, “an” and“the” include plural references unless the content clearly dictatesotherwise. For example, an embodiment including “a compound” should beunderstood to present certain aspects with one compound, or two or moreadditional compounds.

In embodiments comprising an “additional” or “second” component, such asan additional or second compound, the second component as used herein ischemically different from the other components or first component. A“third” component is different from the other, first, and secondcomponents, and further enumerated or “additional” components aresimilarly different.

In understanding the scope of the present application, the term“comprising” and its derivatives, as used herein, are intended to beopen ended terms that specify the presence of the stated features,elements, components, groups, integers, and/or steps, but do not excludethe presence of other unstated features, elements, components, groups,integers and/or steps. The foregoing also applies to words havingsimilar meanings such as the terms, “including”, “having” and theirderivatives. The term “consisting” and its derivatives, as used herein,are intended to be closed terms that specify the presence of the statedfeatures, elements, components, groups, integers, and/or steps, butexclude the presence of other unstated features, elements, components,groups, integers and/or steps. The term “consisting essentially of”, asused herein, is intended to specify the presence of the stated features,elements, components, groups, integers, and/or steps as well as thosethat do not materially affect the basic and novel characteristic(s) offeatures, elements, components, groups, integers, and/or steps.

The term “suitable” as used herein means that the selection of theparticular compound or conditions would depend on the specific syntheticmanipulation to be performed, and the identity of the species to betransformed, but the selection would be well within the skill of aperson trained in the art. All method steps described herein are to beconducted under conditions sufficient to provide the desired product. Aperson skilled in the art would understand that all reaction conditions,including, for example, reaction solvent, reaction time, reactiontemperature, reaction pressure, reactant ratio and whether or not thereaction should be performed under an anhydrous or inert atmosphere, canbe varied to optimize the yield of the desired product and it is withintheir skill to do so.

In embodiments of the present application, the compounds describedherein have at least one asymmetric center. Where compounds possess morethan one asymmetric center, they may exist as diastereomers. It is to beunderstood that all such isomers and mixtures thereof in any proportionare encompassed within the scope of the present application. It is to befurther understood that while the stereochemistry of the compounds maybe as shown in any given compound listed herein, such compounds may alsocontain certain amounts (for example, less than 20%, suitably less than10%, more suitably less than 5%) of compounds of the present applicationhaving alternate stereochemistry. It is intended that any opticalisomers, as separated, pure or partially purified optical isomers orracemic mixtures thereof are included within the scope of the presentapplication.

In embodiments of the present application, the compounds describedherein having a double bond can exist as geometric isomers, for examplecis or trans isomers. It is to be understood that all such geometricisomers and mixtures thereof in any proportion are encompassed withinthe scope of the present application. It is to be further understoodthat while the stereochemistry of these compounds may be as shown in anygiven compound listed herein, such compounds may also contain certainamounts (for example, less than 20%, suitably less than 10%, moresuitably less than 5%) of compounds of the present application havingalternate stereochemistry.

The compounds of the present application can also exist in differenttautomeric forms and it is intended that any tautomeric forms which thecompounds form, are included within the scope of the presentapplication.

The compounds of the present application may further exist in varyingpolymorphic forms and it is contemplated that any polymorphs which form,are included within the scope of the present application.

Terms of degree such as “substantially”, “about” and “approximately” asused herein mean a reasonable amount of deviation of the modified termsuch that the end result is not significantly changed. These terms ofdegree should be construed as including a deviation of at least ±5% ofthe modified term if this deviation would not negate the meaning of theword it modifies or unless the context suggests otherwise to a personskilled in the art.

The expression “proceed to a sufficient extent” as used herein withreference to the reactions or method steps disclosed herein means thatthe reactions or method steps proceed to an extent that conversion ofthe starting material or substrate to product is maximized. Conversionmay be maximized when greater than about 5, 10, 15, 20, 25, 30, 35, 40,45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 or 100% of the startingmaterial or substrate is converted to product.

The term “seven-membered” or “7-membered” as used herein as a prefixrefers to a group having a ring that contains seven ring atoms.

The term “six-membered” or “6-membered” as used herein as a prefixrefers to a group having a ring that contains six ring atoms.

The term “five-membered” or “5-membered” as used herein as a prefixrefers to a group having a ring that contains five ring atoms.

The term “hydrocarbon” as used herein, whether it is used alone or aspart of another group, refers to any structure comprising only carbonand hydrogen atoms up to 14 carbon atoms.

The term “hydrocarbon radical” or “hydrocarbyl” as used herein, whetherit is used alone or as part of another group, refers to any structurederived as a result of removing a hydrogen atom from a hydrocarbon.

The term “hydrocarbylene” as used herein, whether it is used alone or aspart of another group, refers to any structure derived as a result ofremoving a hydrogen atom from two ends of a hydrocarbon.

The term “alkyl” as used herein, whether it is used alone or as part ofanother group, means straight or branched chain, saturated hydrocarbylgroups. For example, the term C₁₋₁₀alkyl means an alkyl group having 1,2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms.

The term “alkylene” as used herein means straight or branched chain,saturated hydrocarbyl group, that is a saturated carbon chain thatcontains substituents on two of its ends. For example, the termC₁₋₁₀alkylene means an alkylene group having 1, 2, 3, 4, 5, 6, 7, 8, 9or 10 carbon atoms.

The term “alkenyl” as used herein, whether it is used alone or as partof another group, means straight or branched chain, unsaturated alkenylgroups. For example, the term C₂₋₁₀alkenyl means an alkenyl group having2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms and at least one double bond,for example 1-3, 1-2 or 1 double bond.

The term “alkenylene” as used herein means straight or branched chain,unsaturated alkenylene group, that is an unsaturated carbon chain thatcontains substituents on two of its ends. For example, the termC₂₋₆alkenylene means an alkenylene group having 2, 3, 4, 5, 6, 7, 8, 9or 10 carbon atoms and at least 1, for example 1-3, 1-2 or 1 doublebond.

The term “alkynyl” as used herein, whether it is used alone or as partof another group, means straight or branched chain unsaturated alkynylgroups. The term C₂₋₆alkynyl means an alkynyl group having 2, 3, 4, 5 or6 carbon atoms and at least one triple bond, for example 1-3, 1-2 or 1triple bond.

The term “alkynylene” as used herein means straight or branched chain,unsaturated alkynylene group, that is an unsaturated carbon chain thatcontains substituents on two of its ends. The term C₂₋₆alkynylene meansan alkynylene group having 2, 3, 4, 5 or 6 carbon atoms and at least 1,for example 1-3, 1-2 or 1 triple bond.

The term “haloalkyl” as used herein refers to an alkyl group wherein oneor more, including all of the hydrogen atoms are replaced by a halogenatom. In an embodiment, the halogen is fluorine, in which case thehaloalkyl is referred to herein as a “fluoroalkyl” group. In anotherembodiment, the haloalkyl comprises at least one —CHF₂ group.

The term “haloalkylene” as used herein refers to an alkylene groupwherein one or more, including all of the hydrogen atoms are replaced bya halogen atom. In an embodiment, the halogen is fluorine, in which casethe haloalkylene is referred to herein as a “fluoroalkylene” group. Inanother embodiment, the haloalkylene comprises a branched fluoroalkylenehaving at least one —CHF₂ group.

The term “cyanoalkyl” as used herein refers to an alkyl group that issubstituted by at least one cyano group. For example, the termC₁₋₁₀cyanoalkyl means an alkyl group having 1, 2, 3, 4, 5, 6, 7, 8, 9 or10 carbon atoms and at least one cyano group attached thereto.

The term “alkoxy” as used herein, whether it is used alone or as part ofanother group, refers to the group “alkyl-O—”. For example, the termC₁₋₁₀alkoxy means an alkyl group having 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10carbon atoms bonded to the oxygen atom of the alkoxy group. Exemplaryalkoxy groups include without limitation methoxy, ethoxy, propoxy,isopropoxy, butoxy, t-butoxy and isobutoxy.

The term “alkenyloxy” as used herein, whether it is used alone or aspart of another group, refers to the group “alkenyl-O—”. For example,the term C₂₋₁₀alkenyloxy means an alkenyl group having 2, 3, 4, 5, 6, 7,8, 9 or 10 carbon atoms and at least one double bond bonded to theoxygen atom of the alkenyloxy group. An exemplary alkoxy group is anallyloxy group.

The term “alkynyloxy” as used herein, whether it is used alone or aspart of another group, refers to the group “alkynyl-O—”. For example,the term C₂₋₁₀alkynyloxy means an alkynyl group having 2, 3, 4, 5, 6, 7,8, 9 or 10 carbon atoms and at least one triple bond bonded to theoxygen atom of the alkynyloxy group. An exemplary alkoxy group is apropargyloxy group.

The term “aryloxy” as used herein, whether it is used alone or as partof another group, refers to the group “aryl-O—”. In an embodiment of thepresent disclosure, the aryl group contains 6, 9, 10 or 14 atoms such asphenyl, naphthyl, indanyl or anthracenyl.

The term “cycloalkyl,” as used herein, whether it is used alone or aspart of another group, means saturated alkyl groups having at least onecyclic ring. For example, the term C₃₋₁₀cycloalkyl means a cycloalkylgroup having 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms.

The term “cycloalkylene” as used herein refers to a cycloalkyl groupthat contains substituents on two of its ends.

The term “aryl” as used herein, whether it is used alone or as part ofanother group, refers to cyclic groups that contain at least onearomatic ring. In an embodiment of the application, the aryl groupcontains from 6, 9, 10 or 14 atoms, such as phenyl, naphthyl, indanyl oranthracenyl.

The term “arylene” as used herein refers to an aryl group that containssubstituents on two of its ends.

The term “heteroarylene” as used herein refers to a heteroaryl groupthat contains substituents on two of its ends.

The term “heterocycloalkyl” as used herein, whether it is used alone oras part of another group, refers to a non-aromatic, ring-containinggroup having one or more multivalent heteroatoms, independently selectedfrom the group consisting of N, O and S, as a part of the ring structureand including at least 3 and up to 20 atoms in the ring(s).Heterocycloalkyl groups are either saturated or unsaturated (i.e.contain one or more double bonds) and may contain more than one ring.When a heterocycloalkyl group contains more than one ring, the rings maybe fused, bridged, spiro connected or linked by a single bond.

A first ring group being “fused” with a second ring group means thefirst ring and the second ring share at least two adjacent atoms therebetween.

A first ring group being “bridged” with a second ring group means thefirst ring and the second ring share at least two non-adjacent atomsthere between.

A first ring group being “spiro connected” with a second ring groupmeans the first ring and the second ring share one atom there between.

Heterocycloalkyl includes monocyclic heterocycloalkyls such as but notlimited to aziridinyl, oxiranyl, thiiranyl, azetidinyl, oxetanyl,thietanyl, pyrrolidinyl, pyrrolinyl, imidazolidinyl, pyrazolidinyl,pyrazolinyl, dioxolanyl, sulfolanyl, 2,3-dihydrofuranyl,2,5-dihydrofuranyl, tetrahydrofuranyl, thiophanyl, piperidinyl,1,2,3,6-tetrahydropyridinyl, piperazinyl, morpholinyl, thiomorpholinyl,pyranyl, thiopyranyl, 2,3-dihydropyranyl, tetrahydropyranyl,1,4-dihydropyridinyl, 1,4-dioxanyl, 1,3-dioxanyl, dioxanyl,homopiperidinyl, 2,3,4,7-tetrahydro-1H-azepinyl, homopiperazinyl,1,3-dioxepanyl, 4,7-dihydro-1,3-dioxepinyl, and hexamethylene oxidyl.Additionally, heterocycloalkyl includes polycyclic heterocycloalkylssuch as but not limited to pyrolizidinyl, and quinolizidinyl. Inaddition to the polycyclic heterocycloalkyls described above,heterocycloalkyl includes polycyclic heterocycloalkyls wherein the ringfusion between two or more rings includes more than one bond common toboth rings and more than two atoms common to both rings. Examples ofsuch bridged heterocycles include but are not limited to quinuclidinyl,diazabicyclo[2.2.1]heptyl and 7-oxabicyclo[2.2.1]heptyl.

The term “heteroaryl” as used herein means a monocyclic ring or apolycyclic ring system containing 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19 or 20 atoms, of which one or more, for example 1 to 8, 1to 6, 1 to 5, or 1 to 4, of the atoms are a heteromoiety selected fromO, S, NH and NC₁₋₆alkyl, with the remaining atoms being C, CH or CH₂,said ring system containing at least one aromatic ring.

Heteroaryl includes for example, pyridinyl, pyrazinyl, pyrimidinyl,pyridazinyl, thienyl, furyl, furazanyl, pyrrolyl, imidazolyl, thiazolyl,oxazolyl, pyrazolyl, isothiazolyl, isoxazolyl, 1,2,3-triazolyl,tetrazolyl, 1,2,3-thiadiazolyl, 1,2,3-oxadiazolyl, 1,2,4-triazolyl,1,2,4-thiadiazolyl, 1,2,4-oxadiazolyl, 1,3,4-triazolyl,1,3,4-thiadiazolyl and 1,3,4 oxadiazolyl.

Heteroaryl also includes polycyclic heteroaryls such as but not limitedto indolyl, indolinyl, isoindolinyl, quinolinyl, tetrahydroquinolinyl,isoquinolinyl, tetrahydroisoquinolinyl, 1,4-benzodioxanyl, coumarinyl,dihydrocoumarinyl, benzofuranyl, 2,3-dihydrobenzofuranyl,isobenzofuranyl, chromenyl, chromanyl, isochromanyl, xanthenyl,phenoxathiinyl, thianthrenyl, indolizinyl, isoindolyl, indazolyl,purinyl, phthalazinyl, naphthyridinyl, quinoxalinyl, quinazolinyl,cinnolinyl, pteridinyl, phenanthridinyl, perimidinyl, phenanthrolinyl,phenazinyl, phenothiazinyl, phenoxazinyl, 1,2-benzisoxazolyl,benzothiophenyl, benzoxazolyl, benzthiazolyl, benzimidazolyl,benztriazolyl, thioxanthinyl, carbazolyl, carbolinyl and acridinyl.

A five-membered heteroaryl is a heteroaryl with a ring having five ringatoms, where 1, 2 or 3 ring atoms are a heteromoiety selected from O, S,NH and NC₁₋₆alkyl, Exemplary five-membered heteroaryls include but arenot limited to thienyl, furyl, pyrrolyl, imidazolyl, thiazolyl,oxazolyl, pyrazolyl, isothiazolyl, isoxazolyl, 1,2,3-triazolyl,tetrazolyl, 1,2,3-thiadiazolyl, 1,2,3-oxadiazolyl, 1,2,4-triazolyl,1,2,4-thiadiazolyl, 1,2,4-oxadiazolyl, 1,3,4-triazolyl,1,3,4-thiadiazolyl, and 1,3,4-oxadiazolyl.

A six-membered heteroaryl is a heteroaryl with a ring having six ringatoms wherein 1, 2 or 3 ring atoms are a heteromoiety selected from O,S, NH and NC₁₋₆alkyl, Exemplary six-membered heteroaryls include but arenot limited to pyridyl, pyrazinyl, pyrimidinyl, triazinyl andpyridazinyl.

The term “cyclic moiety” as used herein refers to any cycloalkyl, aryl,heteroaryl or heterocycloalkyl group as defined herein.

The term “heteromoiety” as used herein refers to a group of atomscontaining at least one heteratom.

As a prefix, the term “substituted” as used herein refers to astructure, molecule or group in which one or more available hydrogenatoms are replaced with one or more other chemical groups. In anembodiment, the chemical group is a C₁₋₄alkyl. In another embodiment,the chemical group is a C₁₋₁₂alkyl or a chemical group that contains oneor more heteroatoms selected from N, O, S, F, Cl, Br, I, and P.Exemplary chemical groups containing one or more heteroatoms includeheterocycloalkyl, heteroaryl, —NO₂, —OR, —R′OR, —Cl, —Br, —I, —F, —CF₃,—C(O)R, —NR₂, —SR, —SO₂R, —S(O)R, —CN, —C(O)OR, —C(O)NR₂, —NRC(O)R,—NRC(O)OR, —R′NR₂, oxo (O), imino (═NR), thio (═S), and oximino (═N—OR),wherein each “R” is hydrogen or a C₁₋₁₂alkyl and “R′” is aC₁₋₁₂alkylene. For example, substituted phenyl may refer to nitrophenyl,pyridylphenyl, methoxyphenyl, chlorophenyl, aminophenyl, etc., whereinthe nitro, pyridyl, methoxy, chloro, and amino groups may replace anyavailable hydrogen on the phenyl ring.

As a suffix, the term “substituted” as used herein in relation to afirst structure, molecule or group, followed by one or more variables ornames of chemical groups, refers to a second structure, molecule orgroup that results from replacing one or more available hydrogen atomsof the first structure, molecule or group with the one or more variablesor named chemical groups. For example, a “phenyl substituted by nitro”refers to nitrophenyl.

The term “available hydrogen atoms” as used herein refers to hydrogenatoms on a molecule or group that can be replaced with another groupunder conditions that will not degrade or decompose the parent compound.Such conditions include the use of protecting groups to protectsensitive functional groups in the molecule while the hydrogen atom isbeing replaced.

The term “optionally substituted” refers to groups, structures, ormolecules that are either substituted or unsubstituted.

The term “amine” or “amino,” as used herein, whether it is used alone oras part of another group, refers to radicals of the general formula—NRR′, wherein R and R′ are each independently selected from hydrogen ora alkyl group, for example C₁₋₆alkyl.

The term “halo” as used herein refers to a halogen atom and includesfluoro, chloro, bromo and iodo.

The term “acac” as used herein refers to acetylacetonate.

The term “atm” as used herein refers to atmosphere.

The term “aq.” as used herein refers to aqueous.

The terms “Boc” and “t-Boc” as used herein refers to the grouptert-butoxycarbonyl.

DCM as used herein refers to dichloromethane.

DIPEA as used herein refers to N,N-diisopropyl ethylamine

DMF as used herein refers to dimethylformamide.

DMSO as used herein refers to dimethylsulfoxide.

EDCl.HCl as used herein refers toN-[3-(dimethylamino)propyl]-N′-ethylcarbodiimide hydrochloride.

EDC as used herein refers to1-ethyl-3-(3-dimethylaminopropyl)carbodiimide.

Et₂O as used herein refers to diethylether.

EtOAc as used herein refers to ethyl acetate.

Et as used herein refers to the group ethyl.

Fmoc as used herein refers to the group 9-fluorenylmethyloxycarbonyl.

The term “hr(s)” as used herein refers to hour(s).

The term “min(s)” as used herein refers to minute(s).

HOBt as used herein refers to N-hydroxybenzotriazole.

HBTU as used herein refers toO-(benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate.

MeOH as used herein refers to methanol.

Me as used herein refers to the group methyl.

t-BuLi as used herein refers to tert-butyllithium.

ON as used herein refers to overnight.

RT as used herein refers to room temperature.

TEA as used herein refers to triethylamine.

TFA as used herein refers to trifluoroacetic acid.

THF as used herein refers to tetrahydrofuran.

t-Bu as used herein refers to the group tertiary butyl.

SPE as used herein refers to solid phase extraction, for example usingcolumns containing silica gel for mini-chromatography.

The term “protecting group” or “PG” and the like as used herein refersto a chemical moiety which protects or masks a reactive portion of amolecule to prevent side reactions in those reactive portions of themolecule, while manipulating or reacting a different portion of themolecule. After the manipulation or reaction is complete, the protectinggroup is removed under conditions that do not degrade or decompose theremaining portions of the molecule. The selection of a suitableprotecting group can be made by a person skilled in the art. Manyconventional protecting groups are known in the art, for example asdescribed in “Protective Groups in Organic Chemistry” McOmie, J. F. W.Ed., Plenum Press, 1973, in Greene, T. W. and Wuts, P. G. M.,“Protective Groups in Organic Synthesis”, John Wiley & Sons, 3^(rd)Edition, 1999 and in Kocienski, P. Protecting Groups, 3rd Edition, 2003,Georg Thieme Verlag (The Americas). Examples of suitable protectinggroups include, but are not limited to t-Boc, cbz, Ac, Ts, Ms, silylethers such as TMSi, TBDMS, TBDPS, Tf, Ns, Bn, Fmoc, benzoyl,dimethoxytrityl, methoxyethoxymethyl ether, methoxymethyl ether,pivaloyl, p-methyoxybenzyl ether, tetrahydropyranyl, trityl, ethoxyethylethers, carbobenzyloxy, benzoyl and the like.

Cbz as used herein refers to the group carboxybenzyl.

Ac as used herein refers to the group acetyl.

Ts (tosyl) as used herein refers to the group p-toluenesulfonyl.

Ms as used herein refers to the group methanesulfonyl.

TMS as used herein refers to tetramethylsilane.

TMSi as used herein refers to the group trimethylsilyl.

TBDMS as used herein refers to the group t-butyldimethylsilyl.

TBDPS as used herein refers to the group t-butyldiphenylsilyl.

Tf as used herein refers to the group trifluoromethanesulfonyl.

Ns as used herein refers to the group naphthalene sulphonyl.

Bn as used herein refers to the group benzyl.

The term “cell” as used herein refers to a single cell or a plurality ofcells and includes a cell either in a cell culture or in a subject.

The term “subject” as used herein includes all members of the animalkingdom including mammals, and suitably refers to humans. Thus themethods and uses of the present application are applicable to both humantherapy and veterinary applications. In an embodiment, the subject is amammal. In another embodiment, the subject is human.

The term “pharmaceutically acceptable” means compatible with thetreatment of subjects, for example humans.

The term “pharmaceutically acceptable carrier” means a non-toxicsolvent, dispersant, excipient, adjuvant or other material which ismixed with the active ingredient in order to permit the formation of apharmaceutical composition, i.e., a dosage form capable ofadministration to a subject. One non-limiting example of such a carrieris a pharmaceutically acceptable oil typically used for parenteraladministration.

The term “pharmaceutically acceptable salt” means either an acidaddition salt or a base addition salt which is suitable for, orcompatible with the treatment of subjects.

An acid addition salt suitable for, or compatible with, the treatment ofsubjects is any non-toxic organic or inorganic acid addition salt of anybasic compound. Basic compounds that form an acid addition salt include,for example, compounds comprising an amine group. Illustrative inorganicacids which form suitable salts include hydrochloric, hydrobromic,sulfuric, nitric and phosphoric acids, as well as acidic metal saltssuch as sodium monohydrogen orthophosphate and potassium hydrogensulfate. Illustrative organic acids which form suitable salts includemono-, di- and tricarboxylic acids. Illustrative of such organic acidsare, for example, acetic, trifluoroacetic, propionic, glycolic, lactic,pyruvic, malonic, succinic, glutaric, fumaric, malic, tartaric, citric,ascorbic, maleic, hydroxymaleic, benzoic, hydroxybenzoic, phenylacetic,cinnamic, mandelic, salicylic, 2-phenoxybenzoic, p-toluenesulfonic acidand other sulfonic acids such as methanesulfonic acid, ethanesulfonicacid and 2-hydroxyethanesulfonic acid. Either the mono- or di-acid saltscan be formed, and such salts can exist in either a hydrated, solvatedor substantially anhydrous form. In general, acid addition salts aremore soluble in water and various hydrophilic organic solvents, andgenerally demonstrate higher melting points in comparison to their freebase forms. The selection criteria for the appropriate salt will beknown to one skilled in the art. Other non-pharmaceutically acceptablesalts such as but not limited to oxalates may be used, for example inthe isolation of compounds of the application for laboratory use, or forsubsequent conversion to a pharmaceutically acceptable acid additionsalt. In another embodiment of the present invention, the compound ofFormula I is converted to a pharmaceutically acceptable salt or solvatethereof, in particular an acid addition salt such as a hydrochloride,hydrobromide, phosphate, acetate, fumarate, maleate, tartrate, citrate,methanesulphonate or p-toluenesulphonate

A base addition salt suitable for, or compatible with, the treatment ofsubjects is any non-toxic organic or inorganic base addition salt of anyacidic compound. Acidic compounds that form a basic addition saltinclude, for example, compounds comprising a carboxylic acid group.Illustrative inorganic bases which form suitable salts include lithium,sodium, potassium, calcium, magnesium or barium hydroxide as well asammonia. Illustrative organic bases which form suitable salts includealiphatic, alicyclic or aromatic organic amines such as isopropylamine,methylamine, trimethylamine, picoline, diethylamine, triethylamine,tripropylamine, ethanolamine, 2-dimethylaminoethanol,2-diethylaminoethanol, dicyclohexylamine, lysine, arginine, histidine,caffeine, procaine, hydrabamine, choline, betaine, ethylenediamine,glucosamine, methylglucamine, theobromine, purines, piperazine,piperidine, N-ethylpiperidine, polyamine resins, and the like. Exemplaryorganic bases are isopropylamine, diethylamine, ethanolamine,trimethylamine, dicyclohexylamine, choline, and caffeine. [See, forexample, S. M. Berge, et al., “Pharmaceutical Salts,” J. Pharm. Sci.1977, 66, 1-19]. The selection of the appropriate salt may be useful sothat an ester functionality, if any, elsewhere in a compound is nothydrolyzed. The selection criteria for the appropriate salt will beknown to one skilled in the art.

Prodrugs of the compounds of the present application may be, forexample, conventional esters formed with available hydroxy, thiol, aminoor carboxyl groups. For example, available hydroxy or amino groups maybe acylated using an activated acid in the presence of a base, andoptionally, in inert solvent (e.g. an acid chloride in pyridine). Somecommon esters which have been utilized as prodrugs are phenyl esters,aliphatic (C₁-C₂₄) esters, acyloxymethyl esters, carbamates and aminoacid esters.

The term “solvate” as used herein means a compound, or a salt or prodrugof a compound, wherein molecules of a suitable solvent are incorporatedin the crystal lattice. A suitable solvent is physiologically tolerableat the dosage administered. Examples of suitable solvents are ethanol,water and the like. When water is the solvent, the molecule is referredto as a “hydrate”. The formation of solvates of the compounds of theapplication will vary depending on the compound and the solvate. Ingeneral, solvates are formed by dissolving the compound in theappropriate solvent and isolating the solvate by cooling or using anantisolvent. The solvate is typically dried or azeotroped under ambientconditions. The selection of suitable conditions to form a particularsolvate can be made by a person skilled in the art.

The term “treating” or “treatment” as used herein and as is wellunderstood in the art, means an approach for obtaining beneficial ordesired results, including clinical results. Beneficial or desiredclinical results can include, but are not limited to alleviation oramelioration of one or more symptoms or conditions, diminishment ofextent of disease, stabilized (i.e. not worsening) state of disease,preventing spread of disease, delay or slowing of disease progression,amelioration or palliation of the disease state, diminishment of thereoccurrence of disease, and remission (whether partial or total),whether detectable or undetectable. “Treating” and “treatment” can alsomean prolonging survival as compared to expected survival if notreceiving treatment. “Treating” and “treatment” as used herein alsoinclude prophylactic treatment. For example, a subject with early cancercan be treated to prevent progression, or alternatively a subject inremission can be treated with a compound or composition described hereinto prevent recurrence. Treatment methods comprise administering to asubject a therapeutically effective amount of one or more of thecompounds of the application and optionally consist of a singleadministration, or alternatively comprise a series of administrations.For example, the compounds of the application may be administered atleast once a week. However, in another embodiment, the compounds may beadministered to the subject from about one time per three weeks, orabout one time per week to about once daily for a given treatment. Inanother embodiment, the compounds are administered 2, 3, 4, 5 or 6 timesdaily. The length of the treatment period depends on a variety offactors, such as the severity of the disease, disorder or condition, theage of the subject, the concentration and/or the activity of thecompounds of the application, and/or a combination thereof. It will alsobe appreciated that the effective dosage of the compound used for thetreatment may increase or decrease over the course of a particulartreatment regime. Changes in dosage may result and become apparent bystandard diagnostic assays known in the art. In some instances, chronicadministration may be required. For example, the compounds areadministered to the subject in an amount and for a duration sufficientto treat the patient.

“Palliating” a disease or disorder means that the extent and/orundesirable clinical manifestations of a disorder or a disease state arelessened and/or time course of the progression is slowed or lengthened,as compared to not treating the disorder.

The term “prevention” or “prophylaxis”, or synonym thereto, as usedherein refers to a reduction in the risk or probability of a patientbecoming afflicted with a disease, disorder or condition mediated byproteasome inhibition or manifesting a symptom associated with adisease, disorder or condition mediated by proteasome inhibition.

As used herein, the term “effective amount” or “therapeuticallyeffective amount” means an amount effective, at dosages and for periodsof time necessary to achieve the desired result. For example in thecontext of treating a disease, disorder or condition mediated byproteasome inhibition, an effective amount is an amount that, forexample, increases proteasome inhibition compared to the proteasomeinhibition without administration of the compound. Effective amounts mayvary according to factors such as the disease state, age, sex and/orweight of the subject. The amount of a given compound that willcorrespond to such an amount will vary depending upon various factors,such as the given drug or compound, the pharmaceutical formulation, theroute of administration, the type of condition, disease or disorder, theidentity of the subject being treated, and the like, but cannevertheless be routinely determined by one skilled in the art.

The term “mediated by” or “associated with” as used herein refers to adisease, disorder or condition in a subject wherein at least one of thecauses is the specified physiological abnormality, for example anenhanced level of proteasome activity, in particular compared tosubjects that do not have the disease, disorder or condition.

The term “administered” as used herein means administration of atherapeutically effective amount of a compound or composition of theapplication to a cell either in cell culture or in a subject.

The term “neoplastic disorder” as used herein refers to a disease,disorder or condition characterized by cells that have the capacity forautonomous growth or replication, e.g., an abnormal state or conditioncharacterized by proliferative cell growth. The term “neoplasm” as usedherein refers to a mass of tissue resulting from the abnormal growthand/or division of cells in a subject having a neoplastic disorder.Neoplasms can be benign (such as uterine fibroids and melanocytic nevi),potentially malignant (such as carcinoma in situ) or malignant (i.e.cancer). Exemplary neoplastic disorders include but are not limited tocarcinoma, sarcoma, metastatic disorders (e.g., tumors arising from theprostate), hematopoietic neoplastic disorders, (e.g., leukemias,lymphomas, myeloma and other malignant plasma cell disorders),metastatic tumors and other cancers. Prevalent cancers include breast,prostate, colon, lung, liver, brain, ovarian and pancreatic cancers.

The term “cancer” as used herein refers to cellular-proliferativedisease states, including but not limited to: Acute LymphoblasticLeukemia, Adult; Acute Lymphoblastic Leukemia, Childhood; Acute MyeloidLeukemia, Adult; Adrenocortical Carcinoma; Adrenocortical Carcinoma,Childhood; AIDS-Related Lymphoma; AIDS-Related Malignancies; AnalCancer; Astrocytoma, Childhood Cerebellar; Astrocytoma, ChildhoodCerebral; Bile Duct Cancer, Extrahepatic; Bladder Cancer; BladderCancer, Childhood; Bone Cancer, Osteosarcoma/Malignant FibrousHistiocytoma; Brain Stem Glioma, Childhood; Brain Tumor, Adult; BrainTumor, Brain Stem Glioma, Childhood; Brain Tumor, CerebellarAstrocytoma, Childhood; Brain Tumor, Cerebral Astrocytoma/MalignantGlioma, Childhood; Brain Tumor, Ependymoma, Childhood; Brain Tumor,Medulloblastoma, Childhood; Brain Tumor, Supratentorial PrimitiveNeuroectodermal Tumors, Childhood; Brain Tumor, Visual Pathway andHypothalamic Glioma, Childhood; Brain Tumor, Childhood (Other); BreastCancer; Breast Cancer and Pregnancy; Breast Cancer, Childhood; BreastCancer, Male; Bronchial Adenomas/Carcinoids, Childhood; Carcinoid Tumor,Childhood; Carcinoid Tumor, Gastrointestinal; Carcinoma, Adrenocortical;Carcinoma, Islet Cell; Carcinoma of Unknown Primary; Central NervousSystem Lymphoma, Primary; Cerebellar Astrocytoma, Childhood; CerebralAstrocytoma/Malignant Glioma, Childhood; Cervical Cancer; ChildhoodCancers; Chronic Lymphocytic Leukemia; Chronic Myelogenous Leukemia;Chronic Myeloproliferative Disorders; Clear Cell Sarcoma of TendonSheaths; Colon Cancer; Colorectal Cancer, Childhood; Cutaneous T-CellLymphoma; Endometrial Cancer; Ependymoma, Childhood; Epithelial Cancer,Ovarian; Esophageal Cancer; Esophageal Cancer, Childhood; Ewing's Familyof Tumors; Extracranial Germ Cell Tumor, Childhood; Extragonadal GermCell Tumor; Extrahepatic Bile Duct Cancer; Eye Cancer, IntraocularMelanoma; Eye Cancer, Retinoblastoma; Gallbladder Cancer; Gastric(Stomach) Cancer; Gastric (Stomach) Cancer, Childhood; GastrointestinalCarcinoid Tumor; Germ Cell Tumor, Extracranial, Childhood; Germ CellTumor, Extragonadal; Germ Cell Tumor, Ovarian; Gestational TrophoblasticTumor; Glioma, Childhood Brain Stem; Glioma, Childhood Visual Pathwayand Hypothalamic; Hairy Cell Leukemia; Head and Neck Cancer;Hepatocellular (Liver) Cancer, Adult (Primary); Hepatocellular (Liver)Cancer, Childhood (Primary); Hodgkin's Lymphoma, Adult; Hodgkin'sLymphoma, Childhood; Hodgkin's Lymphoma During Pregnancy; HypopharyngealCancer; Hypothalamic and Visual Pathway Glioma, Childhood; IntraocularMelanoma; Islet Cell Carcinoma (Endocrine Pancreas); Kaposi's Sarcoma;Kidney Cancer; Laryngeal Cancer; Laryngeal Cancer, Childhood; Leukemia,Acute Lymphoblastic, Adult; Leukemia, Acute Lymphoblastic, Childhood;Leukemia, Acute Myeloid, Adult; Leukemia, Acute Myeloid, Childhood;Leukemia, Chronic Lymphocytic; Leukemia, Chronic Myelogenous; Leukemia,Hairy Cell; Lip and Oral Cavity Cancer; Liver Cancer, Adult (Primary);Liver Cancer, Childhood (Primary); Lung Cancer, Non-Small Cell; LungCancer, Small Cell; Lymphoblastic Leukemia, Adult Acute; LymphoblasticLeukemia, Childhood Acute; Lymphocytic Leukemia, Chronic; Lymphoma,AIDS-Related; Lymphoma, Central Nervous System (Primary); Lymphoma,Cutaneous T-Cell; Lymphoma, Hodgkin's, Adult; Lymphoma, Hodgkin's,Childhood; Lymphoma, Hodgkin's During Pregnancy; Lymphoma,Non-Hodgkin's, Adult; Lymphoma, Non-Hodgkin's, Childhood; Lymphoma,Non-Hodgkin's During Pregnancy; Lymphoma, Primary Central NervousSystem; Macroglobulinemia, Waldenstrom's; Male Breast Cancer; MalignantMesothelioma, Adult; Malignant Mesothelioma, Childhood; MalignantThymoma; Medulloblastoma, Childhood; Melanoma; Melanoma, Intraocular;Merkel Cell Carcinoma; Mesothelioma, Malignant; Metastatic Squamous NeckCancer with Occult Primary; Multiple Endocrine Neoplasia Syndrome,Childhood; Multiple Myeloma/Plasma Cell Neoplasm; Mycosis Fungoides;Myelodysplastic Syndromes; Myelogenous Leukemia, Chronic; MyeloidLeukemia, Childhood Acute; Myeloma, Multiple; MyeloproliferativeDisorders, Chronic; Nasal Cavity and Paranasal Sinus Cancer;Nasopharyngeal Cancer; Nasopharyngeal Cancer, Childhood; Neuroblastoma;Non-Hodgkin's Lymphoma, Adult; Non-Hodgkin's Lymphoma, Childhood;Non-Hodgkin's Lymphoma During Pregnancy; Non-Small Cell Lung Cancer;Oral Cancer, Childhood; Oral Cavity and Lip Cancer; OropharyngealCancer; Osteosarcoma/Malignant Fibrous Histiocytoma of Bone; OvarianCancer, Childhood; Ovarian Epithelial Cancer; Ovarian Germ Cell Tumor;Ovarian Low Malignant Potential Tumor; Pancreatic Cancer; PancreaticCancer, Childhood; Pancreatic Cancer, Islet Cell; Paranasal Sinus andNasal Cavity Cancer; Parathyroid Cancer; Penile Cancer;Pheochromocytoma; Pineal and Supratentorial Primitive NeuroectodermalTumors, Childhood; Pituitary Tumor; Plasma Cell Neoplasm/MultipleMyeloma; Pleuropulmonary Blastoma; Pregnancy and Breast Cancer;Pregnancy and Hodgkin's Lymphoma; Pregnancy and Non-Hodgkin's Lymphoma;Primary Central Nervous System Lymphoma; Primary Liver Cancer, Adult;Primary Liver Cancer, Childhood; Prostate Cancer; Rectal Cancer; RenalCell (Kidney) Cancer; Renal Cell Cancer, Childhood; Renal Pelvis andUreter, Transitional Cell Cancer; Retinoblastoma; Rhabdomyosarcoma,Childhood; Salivary Gland Cancer; Salivary Gland Cancer, Childhood;Sarcoma, Ewing's Family of Tumors; Sarcoma, Kaposi's; Sarcoma(Osteosarcoma)/Malignant Fibrous Histiocytoma of Bone; Sarcoma,Rhabdomyosarcoma, Childhood; Sarcoma, Soft Tissue, Adult; Sarcoma, SoftTissue, Childhood; Sezary Syndrome; Skin Cancer; Skin Cancer, Childhood;Skin Cancer (Melanoma); Skin Carcinoma, Merkel Cell; Small Cell LungCancer; Small Intestine Cancer; Soft Tissue Sarcoma, Adult; Soft TissueSarcoma, Childhood; Squamous Neck Cancer with Occult Primary,Metastatic; Stomach (Gastric) Cancer; Stomach (Gastric) Cancer,Childhood; Supratentorial Primitive Neuroectodermal Tumors, Childhood;T-Cell Lymphoma, Cutaneous; Testicular Cancer; Thymoma, Childhood;Thymoma, Malignant; Thyroid Cancer; Thyroid Cancer, Childhood;Transitional Cell Cancer of the Renal Pelvis and Ureter; TrophoblasticTumor, Gestational; Unknown Primary Site, Cancer of, Childhood; UnusualCancers of Childhood; Ureter and Renal Pelvis, Transitional Cell Cancer;Urethral Cancer; Uterine Sarcoma; Vaginal Cancer; Visual Pathway andHypothalamic Glioma, Childhood; Vulvar Cancer; Waldenstrom's Macroglobulinemia; and Wilms' Tumor. Metastases of the aforementioned cancerscan also be treated in accordance with the methods described herein.

II. Compounds of the Application

Compounds of the present application were prepared and found to inhibituncontrolled and/or abnormal cellular activities affected directly orindirectly by the proteasome. In particular, compounds of the presentapplication exhibited activity as proteasome inhibitors, and aretherefore useful in therapy, for example for the treatment of neoplasticdisorders such as cancer and neurodegenerative disorders associateddirectly or indirectly with proteasome inhibition.

Accordingly, the present application includes a compound of Formula I ora pharmaceutically acceptable salt, solvate or prodrug thereof:

wherein:

R¹ is selected from the group consisting of C₁₋₁₀alkyl, C₂₋₁₀alkenyl,C₂₋₁₀alkynyl, C₁₋₁₀haloalkyl, C₁₋₁₀cyanoalkyl, C₁₋₁₀alkoxy,C₂₋₁₀alkenyloxy, C₂₋₁₀alkynyloxy, C₃₋₁₀cycloalkyl, heterocycloalkyl,aryl, heteroaryl, C₁₋₆alkylene-O—C₁₋₆alkyl,C₁₋₆alkylene-O—C₁₋₆haloalkyl, C₂₋₆alkenylene-O—C₁₋₆haloalkyl,C₂₋₆alkynylene-O—C₁₋₆haloalkyl, C₁₋₆alkylene-C₃₋₈cycloalkyl,C₁₋₆alkylene-heterocycloalkyl, C₁₋₆alkylene-aryl,C₁₋₆alkylene-heteroaryl, C(O)R⁷, OC(O)R⁷, C(O)OR⁷, C₁₋₆alkylene-O—R⁷,C₁₋₆alkylene-C(O)R⁷, C₁₋₆alkylene-O—C(O)R⁷, C₁₋₆alkylene-C(O)OR⁷,C₁₋₆alkylene-O—C(O)OR⁷, C₁₋₆alkylene-NR⁷R⁸, C₁₋₆alkylene-C(O)NR⁷R⁸,C₁₋₆alkylene-NR⁷C(O)R⁸, C₁₋₆alkylene-NR⁷C(O)NR⁷R⁸, C₁₋₆alkylene-S—R⁷,C₁₋₆alkylene-S(O)R⁷, C₁₋₆alkylene-SO₂R⁷, C₁₋₆alkylene-SO₂NR⁷R⁸,C₁₋₆alkylene-NR⁷SO₂R⁸, C₁₋₆alkylene-NR⁷SO₂NR⁷R⁸, C(O)NR⁷R⁸ andC₁₋₆alkylene-NR⁷C(O)OR⁸, wherein any cyclic moiety is optionallysubstituted with C₁₋₄alkyl and/or is optionally fused to a furthercyclic moiety;

X is absent or is selected from the group consisting of O, NH,NC₁₋₆alkyl, S, S(O), SO₂, C(O), C₁₋₆alkylene, C₂₋₆alkenylene,C₂₋₆alkynylene, C₁₋₆haloalkylene, C₃₋₈cycloalkylene,heterocycloalkylene, arylene and heteroarylene, or X is a combination oftwo or three of O, NH, NC₁₋₆alkyl, S, S(O), SO₂, C₁₋₆alkylene,C₂₋₆alkenylene, C₂₋₆alkynylene, C₁₋₆haloalkylene, C₃₋₈cycloalkylene,heterocycloalkylene, arylene or heteroarylene, bonded together in alinear fashion, provided that two or three of O, NH, NC₁₋₆alkyl, S, S(O)and SO₂ and not bonded directly to each other;

R², R³ and R⁴ are each independently selected from the group consistingof C₁₋₁₀alkyl, C₂₋₁₀alkenyl, C₂₋₁₀alkynyl, C₁₋₁₀haloalkyl,C₁₋₁₀cyanoalkyl, C₁₋₁₀alkoxy, C₂₋₁₀alkenyloxy, C₂₋₁₀alkynyloxy,C₃₋₁₀cycloalkyl, heterocycloalkyl, aryl, heteroaryl,C₁₋₆alkylene-O—C₁₋₆alkyl, C₁₋₆alkylene-O—C₁₋₆haloalkyl,C₂₋₆alkenylene-O—C₁₋₆haloalkyl, C₂₋₆alkynylene-O—C₁₋₆haloalkyl,C₁₋₆alkylene-C₃₋₈cycloalkyl, C₁₋₆alkylene-heterocycloalkyl,C₁₋₆alkylene-aryl, C₁₋₆alkylene-heteroaryl, C(O)R⁷, OC(O)R⁷, C(O)OR⁷,C₁₋₆alkylene-O—R⁷, C₁₋₆alkylene-C(O)R⁷, C₁₋₆alkylene-O—C(O)R⁷,C₁₋₆alkylene-C(O)OR⁷, C₁₋₆alkylene-O—C(O)OR⁷, C₁₋₆alkylene-NR⁷R⁸,C₁₋₆alkylene-C(O)NR⁷R⁸, C₁₋₆alkylene-NR⁷C(O)R⁸,C₁₋₆alkylene-NR⁷C(O)NR⁷R⁸, C₁₋₆alkylene-S—R⁷, C₁₋₆alkylene-S(O)R⁷,C₁₋₆alkylene-SO₂R⁷, C₁₋₆alkylene-SO₂NR⁷R⁸, C₁₋₆alkylene-NR⁷SO₂R⁸,C₁₋₆alkylene-NR⁷SO₂NR⁷R⁸, C(O)NR⁷R⁸ and C₁₋₆alkylene-NR⁷C(O)OR⁸, whereinany cyclic moiety is optionally fused to a further 5- to 7-memberedcyclic moiety, wherein at least one of R², R³ and R⁴ isC₁₋₆-alkylene-O—C₁₋₆haloalkyl, and wherein R², R³ and R⁴ are optionallysubstituted with one or more independently-selected R⁶ groups;

R⁵ is selected from the group consisting of H, C₁₋₆alkyl, C₁₋₆haloalkyl,C₂₋₆alkenyl, C₂₋₆alkynyl, C₃₋₈cycloalkyl, C₁₋₆alkylene-C₃₋₈cycloalkyl,aryl, heteroaryl, and heterocycloalkyl;

R⁶ is selected from the group consisting of C₁₋₆alkyl, OH, halo,O—(C₂₋₃alkylene)-O, C₁₋₆alkoxy, aryloxy, —NH—C₁₋₆alkyl, —N(C₁₋₆alkyl)₂,C₁₋₆alkylene-N(C₁₋₆alkyl)₂, C₁₋₆alkylene-NH—C₁₋₆alkyl, cycloalkyl,heterocycloalkyl, aryl and heteroaryl; and

R⁷ and R⁸ are each independently selected from the group consisting ofH, C₁₋₆alkyl, C₁₋₆haloalkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₃₋₁₀cycloalkyl,C₁₋₆alkylene-C₃₋₁₀cycloalkyl, heterocycloalkyl, aryl, C₁₋₆alkylene-aryl,C₁₋₆alkylene-heterocycloalkyl, heteroaryl, and C₁₋₆alkylene-heteroaryl,wherein any cyclic moiety is optionally fused to a further cyclicmoiety.

In an embodiment, R¹ is selected from:

-   -   (i) C₁₋₆alkyl;    -   (ii) C₂₋₁₀alkenyl;    -   (iii) C₂₋₁₀alkynyl;    -   (iv) substituted or unsubstituted C₆₋₁₄aryl;    -   (v) substituted or unsubstituted heteroaryl;    -   (vi) substituted or unsubstituted C₃₋₁₀cycloalkyl; and    -   (vii) substituted or unsubstituted C₃₋₁₀heterocycloalkyl,        wherein the substituents for C₆₋₁₄aryl, heteroaryl,        C₃₋₁₀cycloalkyl and C₃₋₁₀heterocycloalkyl are independently        selected from C₁₋₄alkyl.

In another embodiment, R¹ is selected from:

-   -   (i) C₁₋₆alkyl;    -   (ii) C₂₋₆alkenyl;    -   (iii) C₂₋₆alkynyl;    -   (iv) substituted or unsubstituted C₆₋₁₀aryl;    -   (v) substituted or unsubstituted 5- or 6-membered heteroaryl;    -   (vi) substituted or unsubstituted C₃₋₈cycloalkyl; and    -   (vii) substituted or unsubstituted C₃₋₈heterocycloalkyl,        wherein the substituents for C₆₋₁₀aryl, 5- or 6-membered        heteroaryl, C₃₋₈cycloalkyl and C₃₋₈heterocycloalkyl are        independently selected from C₁₋₄alkyl.

In a further embodiment, R¹ is selected from:

-   -   (i) C₁₋₆alkyl;    -   (ii) a substituted or unsubstituted 5- or 6-membered heteroaryl;        and    -   (iii) C₃-8heterocycloalkyl,        wherein the substituents for the 5- or 6-membered heteroaryl are        independently selected from C₁₋₄alkyl.

It is an embodiment that R¹ is selected from the group consisting of anunsubstituted 5- or 6-membered heteroaryl, a 5- or 6-membered heteroarylsubstituted with a C₁₋₄alkyl and C₃₋₈heterocycloalkyl.

In an embodiment, R¹ is C₁₋₁₀alkyl. In another embodiment, R¹ isC₁₋₆alkyl. In a further embodiment, R¹ is t-butyl.

It is an embodiment that R¹ is an unsubstituted 5- or 6-memberedheteroaryl, a 5-membered heteroaryl substituted with a C₁₋₄alkyl or a6-membered heterocycloalkyl.

In an embodiment, R¹ is heterocycloalkyl. In another embodiment, R¹ isselected from morpholinyl, 1,4-oxazepanyl, thiomorpholinyl,1,4-thiazepanyl, 1,4-thiazepanyl-1-oxide, 1,4-thiazepanyl-1,1-dioxide,1,4-thiazinanyl-1-oxide, 1,4-thiazinanyl-1,1-dioxide, aziridinyl,azetidinyl, pyrrolidinyl, piperazinyl and 1,4-diazepanyl. In anotherembodiment, R¹ is a 6-membered heterocycloalkyl having one O atom andone N atom as a part of the ring structure. It is an embodiment that R¹is morpholinyl. In another embodiment of the present application, R¹ is

In an embodiment, R¹ is an unsubstituted 5- or 6-membered heteroaryl ora 5- or 6-membered heteroaryl substituted with a C₁₋₄alkyl. In anotherembodiment, R¹ is an unsubstituted 5-membered heteroaryl. In a furtherembodiment, R¹ is an unsubstituted 6-membered heteroaryl. It is anembodiment that R¹ is a 5-membered heteroaryl, substituted with aC₁₋₄alkyl. In another embodiment, R¹ is a 5-membered heteroaryl,substituted with a methyl.

In an embodiment, R¹ is selected from:

-   -   (i) substituted or unsubstituted thiazolyl;    -   (ii) substituted or unsubstituted isothiazolyl;    -   (iii) substituted or unsubstituted oxazolyl;    -   (iv) substituted or unsubstituted isooxazolyl;    -   (v) substituted or unsubstituted thiophenyl;    -   (vi) substituted or unsubstituted furanyl;    -   (vii) substituted or unsubstituted 1,2,4-triazolyl;    -   (viii) substituted or unsubstituted pyridyl;    -   (ix) substituted or unsubstituted pyrazinyl;    -   (x) substituted or unsubstituted pyrimidinyl; and    -   (xi) substituted or unsubstituted 1,2,4-triazinyl,        wherein the substituents for thiazolyl, isothiazolyl, oxazolyl,        isooxazolyl, thiophenyl, furanyl, 1,2,4-triazolyl, pyridyl,        pyrazinyl, pyrimidinyl and 1,2,4-triazinyl are independently        selected from a C₁₋₄alkyl such as a methyl.

In another embodiment R¹ is selected from:

-   -   (i) substituted or unsubstituted isoxazolyl;    -   (ii) substituted or unsubstituted isothiazolyl;    -   (iii) substituted or unsubstituted furanyl;    -   (iv) substituted or unsubstituted thiophenyl;    -   (v) substituted or unsubstituted oxazolyl;    -   (vi) substituted or unsubstituted thiazolyl;    -   (vii) substituted or unsubstituted pyrazolyl; and    -   (viii) substituted or unsubstituted imidazolyl,        wherein the substituents for isoxazolyl, isothiazolyl, furanyl,        thiophenyl, oxazolyl, thiazolyl, pyrazolyl and imidazolyl are        independently selected from a C₁₋₄alkyl such as a methyl.

In another embodiment, R¹ is selected from:

-   -   (i) substituted or unsubstituted isoxazolyl;    -   (ii) substituted or unsubstituted furanyl; and    -   (iii) substituted or unsubstituted thiazolyl,        wherein the substituents for isooxazolyl, furanyl and thiazolyl        are independently selected from a C₁₋₄alkyl such as a methyl.

In another embodiment, R¹ is selected from:

In an embodiment, X is absent or is selected from O, NH, NC₁₋₆alkyl, S,C₁₋₆alkylene, C₂₋₆alkenylene and C₂₋₆alkynylene. In another embodiment,X is absent. In a further embodiment, X is O or C₁₋₆alkylene. It is anembodiment that X is O. In another embodiment, X is C₁₋₄alkylene. In afurther embodiment X is —CH₂—.

In an embodiment, X is O and R¹ is C₁₋₆alkyl. In another embodiment, Xis O and R¹ is t-butyl.

In another embodiment, X is C₁₋₆alkylene and R¹ is C₃₋₈heterocycloalkyl.In a further embodiment, X is C₁₋₄alkylene and R¹ is a 6-memberedheterocycloalkyl. It is an embodiment of the present application that Xand R¹ together form the structure:

In other embodiments, X is absent and R¹ is substituted or unsubstitutedheteroaryl, wherein the substituents for heteroaryl are independentlyselected from a C₁₋₄alkyl such as a methyl. It will be appreciated thatin such embodiments of the present application, the heteroarylembodiments can be as discussed above in respect of R¹.

In an embodiment, R², R³ and R⁴ are each independently selected from thegroup consisting of C₁₋₁₀alkyl, C₂₋₁₀alkenyl, C₂₋₁₀alkynyl,C₁₋₆alkyleneC₆₋₁₄aryl, C₁₋₆alkylene-heteroaryl,C₁₋₆alkyleneC₃₋₈cycloalkyl, C₁₋₆alkylene-O—C₁₋₆alkyl,C₁₋₆alkylene-O—C₁₋₆haloalkyl, C₂₋₆alkenylene-O—C₁₋₆haloalkyl andC₂₋₆alkynylene-O—C₁₋₆haloalkyl, wherein at least one of R², R³ and R⁴ isC₁₋₆-alkylene-O—C₁₋₆haloalkyl. In another embodiment, R², R³ and R⁴ areeach independently selected from the group consisting of C₁₋₆alkyl,C₁₋₆alkyleneC₆₋₁₀aryl, C₁₋₆alkylene-O—C₁₋₄alkyl andC₁₋₆alkylene-O—C₁₋₄fluoroalkyl, wherein at least one of R², R³ and R⁴ isC₁₋₆alkylene-O—C₁₋₄fluoroalkyl. In a further embodiment R², R³ and R⁴are each independently selected from the group consisting of C₁₋₆alkyl,C₁₋₄alkylene-phenyl, C₁₋₄alkylene-O—C₁₋₄alkyl, C₁₋₄alkylene-O—CH₂F,C₁₋₄alkylene-O—CHF₂ and C₁₋₄alkylene-O—CF₃, wherein at least one of R²,R³ and R⁴ is C₁₋₄alkylene-O—CH₂F, C₁₋₄alkylene-O—CHF₂ orC₁₋₄alkylene-O—CF₃. It is an embodiment that R², R³ and R⁴ are eachindependently selected from the group consisting of isobutyl, —CH₂-Ph,—CH₂—O—CH₃, —CH₂—O—CH₂F, —CH₂—O—CHF₂ and —CH₂—O—CF₃, wherein at leastone of R², R³ and R⁴ is —CH₂—O—CH₂F, —CH₂—O—CHF₂ or —CH₂—O—CF₃ Inanother embodiment, R², R³ and R⁴ are each independently selected fromthe group consisting of isobutyl, —CH₂-Ph, —CH₂—O—CH₃ and —CH₂—O—CHF₂,wherein at least one of R², R³ and R⁴ is —CH₂—O—CHF₂.

In an embodiment, R² and R³ are each independently selected from thegroup consisting of C₁₋₁₀alkyl, C₂₋₁₀alkenyl, C₂₋₁₀alkynyl,C₁₋₆alkylene-O—C₁₋₆alkyl, C₁₋₆alkylene-O—C₁₋₆haloalkyl,C₂₋₆alkenylene-O—C₁₋₆haloalkyl and C₂₋₆alkynylene-O—C₁₋₆haloalkyl,wherein at least one of R² and R³ is C₁₋₆-alkylene-O—C₁₋₆haloalkyl. Inanother embodiment, R² and R³ are each independently selected from thegroup consisting of C₁₋₆alkyl, C₁₋₆alkylene-O—C₁₋₄alkyl andC₁₋₆alkylene-O—C₁₋₄fluoroalkyl, wherein at least one of R² and R³ isC₁₋₆alkylene-O—C₁₋₄fluoroalkyl. In a further embodiment R² and R³ areeach independently selected from the group consisting of C₁₋₆alkyl,C₁₋₄alkylene-O—C₁₋₄alkyl, C₁₋₄alkylene-O—CH₂F, C₁₋₄alkylene-O—CHF₂ andC₁₋₄alkylene-O—CF₃ wherein at least one of R² and R³ isC₁₋₄alkylene-O—CH₂F, C₁₋₄alkylene-O—CHF₂ or C₁₋₄alkylene-O—CF₃. It is anembodiment that R² and R³ are each independently selected from the groupconsisting of isobutyl, —CH₂—O—CH₃, —CH₂—O—CH₂F, —CH₂—O—CHF₂ and—CH₂—O—CF₃, wherein at least one of R² and R³ is —CH₂—O—CH₂F,—CH₂—O—CHF₂ or —CH₂—O—CF₃. In another embodiment, R² and R³ are eachindependently selected from the group consisting of isobutyl, —CH₂—O—CH₃and —CH₂—O—CHF₂, wherein at least one of R² and R³ is —CH₂—O—CHF₂.

In an embodiment, R² and R³ are each C₁₋₆alkylene-O—C₁₋₄fluoroalkyl. Inanother embodiment, R² and R³ are each C₁₋₄alkylene-O—CHF₂. In a furtherembodiment, R² and R³ are each —CH₂—O—CHF₂.

In an embodiment, R⁴ is selected from the group consisting ofC₁₋₁₀alkyl, C₂₋₁₀alkenyl, C₂₋₁₀alkynyl, C₁₋₆alkyleneC₃₋₈cycloalkyl andC₁₋₆alkyleneC₆₋₁₄aryl. In another embodiment, R⁴ is selected from thegroup consisting of C₁₋₆alkyl, C₁₋₆alkyleneC₃₋₈cycloalkyl, andC₁₋₆alkyleneC₆₋₁₀aryl. In a further embodiment, R⁴ is selected from thegroup consisting of C₁₋₆alkyl and C₁₋₄alkylene-phenyl. It is anembodiment that R⁴ is isobutyl or —CH₂-Ph. In an embodiment, R⁴ isisobutyl. In another embodiment, R⁴ is —CH₂-Ph.

In another embodiment, at least one of R² and R³ or both isindependently selected from the group consisting of C₁₋₆alkylene-O—CH₂F,C₁₋₆alkylene-O—CHF₂ and C₁₋₆alkylene-O—CF₃. In a further embodiment, atleast one of R² and R³ or both is —CH₂—O—CHF₂.

In another embodiment, R⁴ is selected from C₁₋₆alkyl,C₁₋₆alkyleneC₃₋₈cycloalkyl and C₁₋₆alkyleneC₆₋₁₄aryl, optionallysubstituted with one or more independently-selected groups R⁶. In afurther embodiment, R⁴ is selected from —CH₂-phenyl —(CH₂)₂-phenyl,isobutyl, and tert-butyl. It is an embodiment that R⁴ is —CH₂-phenyl orisobutyl.

In an embodiment, R⁵ is selected from the group consisting of H,C₁₋₆alkyl, C₂₋₆alkenyl and C₂₋₆alkynyl. In another embodiment, R⁵ isC₁₋₆alkyl. In a further embodiment, R⁵ is C₁₋₄alkyl. It is an embodimentthat R⁵ is methyl.

In an embodiment, R⁶ is selected from the group consisting of C₁₋₄alkyl,OH, C₁₋₄alkoxy, C₆₋₁₀aryloxy, —NH—C₁₋₄alkyl, —N(C₁₋₄alkyl)₂,C₁₋₄alkylene-N(C₁₋₄alkyl)₂, C₁₋₄alkylene-NH—C₁₋₄alkyl, C₃₋₈cycloalkyl,heterocycloalkyl, C₆₋₁₀aryl and a 5- or 6-membered heteroaryl. Inanother embodiment, R⁶ is selected from the group consisting ofC₁₋₄alkyl, OH, C₁₋₄alkoxy, —NH—C₁₋₄alkyl and —N(C₁₋₄alkyl)₂.

In an embodiment, R⁷ and R⁸ are each independently selected from thegroup consisting of H, C₁₋₄alkyl, C₁₋₄haloalkyl, C₂₋₄alkenyl,C₂₋₄alkynyl, C₃₋₈cycloalkyl, C₁₋₄alkylene-C₃₋₈cycloalkyl,heterocycloalkyl, C₆₋₁₀aryl, C₁₋₄alkylene-C₆₋₁₀aryl,C₁₋₄alkylene-heterocycloalkyl, heteroaryl, and C₁₋₄alkylene-heteroaryl,wherein any cyclic moiety is optionally fused to a further 5- to7-membered heterocycloalkyl.

In an embodiment, the compounds of Formula I have the following relativestereochemistry:

In an embodiment, the compound of the present application is selectedfrom the compounds of Examples 1 to 33 as illustrated below or apharmaceutically acceptable salt, solvate or prodrug thereof:

-   2-Methyl-thiazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   2-Methyl-thiazole-5-carboxylic    acid-((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-methoxy-ethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   2-Methyl-thiazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-methoxyethyl)-amide;-   2-Methyl-oxazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   3-Methyl-isoxazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   Thiazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxoethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)amide;-   Oxazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   5-Methyl-thiophene-2-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   5-Methyl-furan-2-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   Thiophene-2-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   N-[(1S)-2-[[(1S)-2-[[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]amino]-1    (difluoromethoxymethyl)-2-oxo-ethyl]amino]-1-(difluoromethoxymethyl)-2-oxo-ethyl]-1H-1,2,4-triazole-5-carboxamide;-   N-[(1S)-1-(difluoromethoxymethyl)-2-[[(1S)-1-(difluoromethoxymethyl)-2-[[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]-amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]-2-methyl-thiazole-5-carboxamide;-   Pyridine-2-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   N—((S)-1-{(S)-1-[(S)-1-Benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-nicotinamide;-   Pyridine-2-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   N-[(1S)-2-[[(1S)-2-[[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]amino]-1-(difluoromethoxymethyl)-2-oxo-ethyl]amino]-1-(difluoromethoxymethyl)-2-oxo-ethyl]-pyrimidine-2-carboxamide;-   [1,2,4]Triazine-3-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   Pyrimidine-4-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   2-Methyl-thiazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-3-methylbutylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   2-Methyl-thiazole-5-carboxylic acid    ((S)-2-difluoromethoxy-1-{(S)-3-methyl-1-[(S)-3-methyl-1-((R)-2-methyloxiranecarbonyl)-butylcarbamoyl]-butylcarbamoyl}-ethyl)-amide,-   2-Methyl-thiazole-5-carboxylic acid    ((S)-1-{(S)-2-difluoromethoxy-1-[(S)-3-methyl-1-((R)-2-methyloxiranecarbonyl)-butylcarbamoyl]-ethylcarbamoyl}-3-methylbutyl)-amide;-   2-Methyl-thiazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-3-methylbutyl)-amide;-   2-Methyl-thiazole-5-carboxylic acid    ((S)-1-{(S)-2-difluoromethoxy-1-[(S)-3-methyl-1-((R)-2-methyloxiranecarbonyl)-butylcarbamoyl]-ethylcarbamoyl}-2-phenylethyl)-amide;-   2-Methyl-thiazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-phenylethyl)-amide;-   2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-N-[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]-3-phenylpropanamide;-   (S)—N—{(S)-1-[(S)-1-Benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethyl-carbamoyl]-2-difluoromethoxyethyl}-3-difluoromethoxy-2-(2-morpholin-4-yl-acetylamino)-propionamide;-   (2S)—N-[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-4-methylpentanamide;-   (2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-4-methyl-N-[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]pentanamide;-   (2S)—N-[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-3-(1-methylcyclohexa-1,3,5-trien-1-yl)propanamide;-   (S)-4-Methyl-2-(2-morpholin-4-yl-acetylamino)-pentanoic acid    {(S)-2-difluoromethoxy-1-[(S)-3-methyl-1-((R)-2-methyloxiranecarbonyl)-butylcarbamoyl]-ethyl}-amide;-   (S)-4-Methyl-2-(2-morpholin-4-yl-acetylamino)-pentanoic acid    {(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethyl}-amide;-   (2S)—N-[(1S)-2-[[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]amino]-1(difluoromethoxymethyl)-2-oxo-ethyl]-2-[(2-morpholinoacetyl)amino]-3-phenylpropanamide;    and-   (2S)-3-(difluoromethoxy)-N-[(1S)-1-(difluoromethoxymethyl)-2-[[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]amino]-2-oxo-ethyl]-2-[(2-morpholinoacetyl)amino]-propanamide.

In another embodiment, the compound of the present application isselected from:

-   2-Methyl-thiazole-5-carboxylic acid    ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;-   (2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-N-[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]-3-phenyl-propanamide;-   (S)—N—{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethyl}-3-difluoromethoxy-2-(2-morpholin-4-yl-acetylamino)-propionamide;-   (2S)—N-[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-4-methylpentanamide;-   (2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholino-acetyl)amino]propanoyl]amino]-4-methyl-N-[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]pentanamide;-   (2S)—N-[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-3-(1-methylcyclohexa-1,3,5-trien-1-yl)propanamide;    and-   (2S)-3-(difluoromethoxy)-N-[(1S)-1-(difluoromethoxymethyl)-2-[[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]amino]-2-oxo-ethyl]-2-[(2-morpholinoacetyl)amino]propanamide.

In another embodiment, the compound of the present application is2-methyl-thiazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide.

In an embodiment, the present application also includes a compound ofFormula (I):

wherein:

R¹ is selected from the group consisting of C₁₋₆-alkyl, C₁₋₆-alkyloxy,C₁₋₆-alkyloxyoalkyl, C₁₋₆-alkenyloxyhaloalkyl, C₁₋₆-alkynyloxyhaloalkyl,C₁₋₆-alkylhalo, C₂₋₆-alkenyl, C₂₋₆-alkynyl, C₃₋₈-cycloalkyl,C₁₋₆-alkyl-C₃₋₈-cycloalkyl, aryl, heteroaryl, C₁₋₆-alkylaryl,C₁₋₆-alkylheteroaryl, C₁₋₆-alkylheterocycloalkyl, C(O)H, (CO)R⁷,O(CO)R⁷, C(O)OR⁷, C₁₋₆-alkylOR⁷, C₁₋₆-alkyl(CO)R⁷, C₀₋₆-alkylCO₂R⁷,C₁₋₆-alkylcyano, C₁₋₆-alkylNR⁷R⁸, C₁₋₆-alkyl(CO)NR⁷R⁸,C₁₋₆-alkylNR⁶(CO)R⁸, C₁₋₆-alkylNR⁷(CO)NR⁷R⁸, C₁₋₆-alkylSR⁷,C₁₋₆-alkyl(SO)R⁷, C₁₋₆-alkylSO₂R⁶, C₁₋₆-alkyl(SO₂)NR⁷R⁸,C₁₋₆-alkylNR⁷(SO₂)R⁸, C₁₋₆-alkylNR⁷(SO₂)NR⁷R⁸, (CO)NR⁷R⁸,C₁₋₆-alkylNR⁷(CO)OR⁸, and a 3- to 7-membered ring that may contain oneor more heteroatoms independently selected from the group consisting ofN, O and S, wherein any cyclic moiety is optionally fused to a 5- to7-membered ring that may contain one or more heteroatoms independentlyselected from the group consisting of N, O and S;

X is selected from the group consisting of hydrogen, carbon, oxygen,nitrogen, sulfur, C₁₋₆-alkyl, C₁₋₆-alkyloxy, C₁₋₆-alkyloxyoalkyl,C₁₋₆-alkenyloxyamminoalkyl, C₁₋₆-alkynyloxyhaloalkyl, C₁₋₆-alkylhalo,C₂₋₆-alkenyl, C₂₋₆-alkynyl, C₃₋₈-cycloalkyl, C₁₋₆-alkyl-C₃₋₈-cycloalkyl,aryl, heteroaryl, C₁₋₆-alkylaryl, C₁₋₆-alkylheteroaryl,C₁₋₆-alkylheterocycloalkyl;

R², R³ and R⁴, are selected from the group consisting of C₁₋₆-alkyl,C₁₋₆-alkyloxy, C₁₋₆-alkyloxyoalkyl, C₁₋₆-alkenyloxyhaloalkyl,C₁₋₆-alkynyloxyhaloalkyl, C₁₋₆-alkylhalo, C₂₋₆-alkenyl, C₂₋₆-alkynyl,C₃₋₈-cycloalkyl, C₁₋₆-alkyl-C₃₋₈-cycloalkyl, aryl, heteroaryl,C₁₋₆-alkylaryl, C₁₋₆-alkylheteroaryl, C₁₋₆-alkylheterocycloalkyl, C(O)H,(CO)R⁷, O(CO)R⁷, C(O)OR⁷, C₁₋₆-alkylOR⁷, C₁₋₆-alkyl(CO)R⁷,C₀₋₆-alkylCO₂R⁷, C₁₋₆-alkylcyano, C₁₋₆-alkylNR⁷R⁸, C₁₋₆-alkyl(CO)NR⁷R⁸,C₁₋₆-alkylNR⁶(CO)R⁸, C₁₋₆-alkylN⁷(CO)NR⁷R⁸, C₁₋₆-alkylSR⁷,C₁₋₆-alkyl(SO)R⁷, C₁₋₆-alkylSO₂R⁶, C₁₋₆-alkyl(SO₂)NR⁷R⁸,C₁₋₆-alkylNR⁷(SO₂)R⁸, C₁₋₆-alkylNR⁷(SO₂)NR₇R⁸, (CO)NR⁷R⁸,C₁₋₆-alkylNR⁷(CO)OR⁸, and a 3- to 7-membered ring that may contain oneor more heteroatoms independently selected from the group consisting ofN, O and S, wherein any cyclic moiety is optionally fused to a 5- to7-membered ring that may contain one or more heteroatoms independentlyselected from the group consisting of N, O and S; with the proviso thatat least R², R³ or R⁴ is C₁₋₆-alkyloxyhaloalkyl, optionally substitutedwith one or more independently-selected groups R⁶; and cannotsimultaneously be C₁₋₆-alkyloxyoalkyl;

R⁵, is selected from the group consisting of H, C₁₋₆-alkyl,C₁₋₆-alkylhalo, C₂₋₆-alkenyl, C₂₋₆-alkynyl, C₃₋₈-cycloalkyl,C₁₋₆-alkyl-C₃₋₈-cycloalkyl, aryl, heteroaryl, and a 3- to 7-memberedring that may contain one or more heteroatoms independently selectedfrom the group consisting of N, O and S;

R⁶ is selected from the group consisting of H, C₁₋₆-alkyl, F, Cl, Br, I,OH, —O—(CH₂)_(2,3)—O—, OC₁₋₆-alkyl, OC₁₋₆-aryl, NH—C₁₋₆-alkyl, andN(C₁₋₆-alkyl)₂, C₁₋₆-alkyl-N(C₁₋₆-alkyl)₂, C₁₋₆-alkyl-NH—C₁₋₆-alkylcycloalkyl, heterocycloalkyl, aryl and heteroaryl;

R⁷ and R⁸ are independently selected from the group consisting of H,C₁₋₆-alkyl, C₁₋₆-alkylhalo, C₂₋₆-alkenyl, C₂₋₆-alkynyl, C₃₋₈-cycloalkyl,C₁₋₆-alkyl-C₃₋₈-cycloalkyl, cycloalkyl, aryl, C₁₋₆-alkylaryl,C₀₋₆-alkyl-heterocycloalkyl, heteroaryl, and C₁₋₆alkylheteroaryl,wherein any cyclic moiety is optionally fused to a 5- to 7-membered ringthat may contain one or more heteroatoms independently selected from thegroup consisting of C, N, O and S.

In an embodiment, X is C₀₋₇ alkyl and R¹ is a 5- or -6 memberedheteroaryl and acyclic and 3-7-membered amine.

In another embodiment, X is C₀₋₇ alkyl, R¹ is selected from morpholine,1,4-oxazepane, thiomorpholine, 1,4-thiazepane, 1,4-thiazepane 1-oxide,1,4-thiazepane 1,1-dioxide, 1,4-thiazinane 1-oxide, 1,4-thiazinane1,1-dioxide, aziridine, azetidine, pyrrolidine, piperazine and1,4-diazepane, oxadiazole isoxazole, isothiazole, furan, thiophene,oxazole, thiazole, pyrazole, and imidazole.

In another embodiment, at least one of R², R³ or R⁴ is selected fromC₁₋₆ alkoxyhaloalkyl, in a further certain aspect, at least one of R²,R³ and R⁴ or all is selected from mono-fluoromethyl, di-fluoromethyl andtri-fluoromethyl moiety groups.

In another embodiment, at least one of R² and R³ is selected fromC₁₋₆-alkoxyhaloalkyl, in a further certain aspect, at least one of R²and R³ or both are selected from di-fluoromethyl, moiety.

In another embodiment, R⁴ is selected from C₁₋₆ alkyl, C₁₋₆ alkyl, C₁₋₆alkylcycloalkyl and C₁₋₆ alkylaryl. In certain such embodiment, R⁴ isselected from phenylmethyl, phenyl-ethyl, 2-methyl-butanyl,2,2-dimethyl-butanyl, preferably phenyl-methyl and 2-Methyl-butanyl.

III. Preparation of Compounds of the Application

Compounds of the present application can be prepared by varioussynthetic processes. The choice of particular structural features and/orsubstituents may influence the selection of one process over another.The selection of a particular process to prepare a given compound ofFormula I is within the purview of the person of skill in the art. Somestarting materials for preparing compounds of the present applicationare available from commercial chemical sources. Other startingmaterials, for example as described below, are readily prepared fromavailable precursors using straightforward transformations that are wellknown in the art.

In an embodiment, the compounds of Formula I are generally preparedaccording to the process illustrated in Scheme I. Variables in thefollowing schemes are as defined above for Formula I unless otherwisespecified.

In an embodiment, as shown in Scheme 1, the compounds of the presentapplication are prepared by coupling of a dipeptide of Formula II withan epoxyketone of Formula III via the formation of a peptide bond.Methods for coupling compounds through peptide (amide) bonds are wellknown in the art and described, for example, in The Peptides: Analysis,Synthesis, Biology, Vol. I., eds. Academic Press, 1979.

In an embodiment, the intermediate compound of Formula II is preparedaccording to standard procedures for peptide bond formation asillustrated in Scheme II, wherein the compounds of Formula IV and V arecoupled via amide bond formation. For example, the compounds of FormulaIV (wherein R¹ is optionally a protecting group, such as Boc or Cbz) andFormula V (wherein A is, for example an alkyl or benzyl group) areobtained from commercial sources or prepared by methods known in theart. Examples of the dipeptide of Formula II are provided in specificexamples described below.

In an embodiment, epoxyketones of Formula III are prepared asillustrated in Scheme III using modified literature methods [see, forexample, Bioorg. Med. Chem. Lett. 2007, 17, 6169-6171; Bioorg. Med.Chem. Lett. 1999, 9, 2283-2288; Eur. J. Org. Chem. 2005, 4829-4834; andJ. Med. Chem. 2009, 52, 3028-3038].

As shown in Scheme III, epoxyketone compounds of Formula III, in oneembodiment, are prepared from a protected amino acid of Formula VI whichis transformed to the corresponding Weinreb amide of Formula VII [see,for example, Synthesis 1983, 676; Bioorg. Med. Chem. Lett. 1999,2283-2288], followed by an appropriate lithium, zinc or Grignard reagentcondensation leading to the unsaturated ketone of Formula VIII.Subsequent epoxidation with alkaline hydrogen peroxide provides epoxidederivatives of Formula IX as a mixture of diastereomers, which arereadily separated by column chromatography. Removal of the protectinggroup (PG) by a suitable method such as a hydrogenolysis reaction (forexample, wherein PG is a Cbz group) or hydrolysis in acidic conditions(for example, wherein PG is a Boc protecting group), gives the epoxidesof Formula III in salt form, such as a salt of TFA.

In an alternative embodiment, according to Scheme IV, epoxyketoneintermediates of Formula III are prepared from an unsaturated ketone ofFormula VIII, which is reduced to the corresponding allylic alcohol ofFormula X. Subsequently, Sharpless asymmetric epoxidation leads tohydroxyl-ketone compounds of Formula XI which are oxidized to provideepoxyketone intermediates of Formula IX, which are subsequentlyhydrolyzed to provide intermediate compounds of Formula III [see, forexample, J. Med. Chem. 2009, 52, 3028-3038; Tetrahedron: Asymmetry 2001,12, 943-947].

In an embodiment, as a representative example of the incorporation of aC₁₋₆alkylene-O—C₁₋₆haloalkyl group in R², R³ and/or R⁴ of the compoundsof the application, a precursor compound to the compounds of Formula I,for example a compound of the Formula II, III, IV or V, or protectedforms thereof, wherein R², R³ and/or R⁴ is C₁₋₆alkylene-OH is reactedwith, for example, 2-fluorosulfonyldifluoroacetic acid in the presenceof a metal catalyst, such as copper (I) iodide, under conditions tocovert the C₁₋₆alkylene-OH to C₁₋₆alkylene-OCHF₂. A person skilled inthe art would know other methods of functionalizing the C₁₋₆alkylene-OHgroup with alternative C₁₋₆haloalkyl group using methods and reagentsavailable in the art.

Another aspect of the present application provides processes forpreparing compounds of Formula I, or salts, solvates or prodrugsthereof. Processes for the preparation of the compounds in the presentapplication are described herein.

Accordingly, the present application includes a method for preparing acompound of Formula I comprising reacting a compound of a Formula IIwith a compound of a Formula III:

Wherein R¹, R², R³, R⁴ and R⁵ are as defined above for the compounds ofFormula I, or are protected forms thereof,under conditions for the formation of an amide bond; andremoval of protecting groups if present.

In another embodiment, the compounds of Formula II are prepared byreacting a compound of the Formula VIII:

wherein PG is a protecting group and R⁴ and R⁵ are as defined above forthe compounds of Formula I, or are protected forms thereof,under conditions for the epoxidation of the double bond followed byremoval of protecting groups.

In an alternative embodiment, the compounds of Formula II are preparedby reacting a compound of the Formula VIII:

wherein PG is a protecting group and R⁴ and R⁵ are as defined above forthe compounds of Formula I, or are protected forms thereof,under conditions for the reduction of the ketone to the correspondingalcohol, followed by epoxidation of the double bond, followed byoxidation of the alcohol and then removal of protecting groups.

In addition, it is intended that the present application cover compoundsmade either using standard organic synthetic techniques, includingcombinatorial chemistry or by biological methods, such as bacterialdigestion, metabolism, enzymatic conversion, and the like.

Throughout the processes described herein it is to be understood that,where appropriate, suitable protecting groups will be added to, andsubsequently removed from, the various reactants and intermediates in amanner that will be readily understood by one skilled in the art.Conventional procedures for using such protecting groups as well asexamples of suitable protecting groups are described, for example, in“Protective Groups in Organic Synthesis”, T. W. Green, P. G. M. Wuts,Wiley-lnterscience, New York, (1999). It is also to be understood that atransformation of a group or substituent into another group orsubstituent by chemical manipulation can be conducted on anyintermediate or final product on the synthetic path toward the finalproduct, in which the possible type of transformation is limited only byinherent incompatibility of other functionalities carried by themolecule at that stage to the conditions or reagents employed in thetransformation. Such inherent incompatibilities, and ways to circumventthem by carrying out appropriate transformations and synthetic steps ina suitable order, will be readily understood to one skilled in the art.Examples of transformations are given herein, and it is to be understoodthat the described transformations are not limited only to the genericgroups or substituents for which the transformations are exemplified.References and descriptions of other suitable transformations are givenin “Comprehensive Organic Transformations—A Guide to Functional GroupPreparations” R. C. Larock, VHC Publishers, Inc. (1989). References anddescriptions of other suitable reactions are described in textbooks oforganic chemistry, for example, “Advanced Organic Chemistry”, March, 4thed. McGraw Hill (1992) or, “Organic Synthesis”, Smith, McGraw Hill,(1994). Techniques for purification of intermediates and final productsinclude, for example, straight and reversed phase chromatography oncolumn or rotating plate, recrystallisation, distillation andliquid-liquid or solid-liquid extraction, which will be readilyunderstood by one skilled in the art.

IV. Compositions

The compounds of the present application are suitably formulated in aconventional manner into compositions using one or more carriers.Accordingly, the present application also includes a compositioncomprising one or more compounds of the application and a carrier. Inanother embodiment, the compounds of the application are suitablyformulated into pharmaceutical compositions for administration tosubjects in a biologically compatible form suitable for administrationin vivo. Accordingly, the present application further includes apharmaceutical composition comprising one or more compounds of theapplication and a pharmaceutically acceptable carrier.

The compounds of the application are administered to a subject in avariety of forms depending on the selected route of administration, aswill be understood by those skilled in the art. A compound of theapplication is administered, for example, by oral, parenteral, buccal,sublingual, nasal, rectal, patch, pump or transdermal administration andthe pharmaceutical compositions formulated accordingly. In anembodiment, administration is by means of a pump for periodic orcontinuous delivery.

Parenteral administration includes intravenous, intra-arterial,intraperitoneal, subcutaneous, intramuscular, transepithelial, nasal,intrapulmonary (for example, by use of an aerosol), intrathecal, rectaland topical (including the use of a patch or other transdermal deliverydevice) modes of administration. In an embodiment, parenteraladministration is by continuous infusion over a selected period of time.Conventional procedures and ingredients for the selection andpreparation of suitable compositions are described, for example, inRemington's Pharmaceutical Sciences (2000-20th edition) and in TheUnited States Pharmacopeia: The National Formulary (USP 24 NF19)published in 1999.

In an embodiment, a compound of the application is orally administered,for example, with an inert diluent or with an assimilable ediblecarrier, or it is enclosed in hard or soft shell gelatin capsules, or itmay be compressed into tablets, or it is incorporated directly with thefood of the diet. In a further embodiment, for oral therapeuticadministration, the compound is incorporated with excipient and used inthe form of ingestible tablets, buccal tablets, troches, capsules,caplets, pellets, granules, lozenges, chewing gum, powders, syrups,elixirs, wafers, aqueous solutions or suspensions, and the like. In thecase of tablets, carriers that are used include lactose, corn starch,sodium citrate and salts of phosphoric acid. Pharmaceutically acceptableexcipients include binding agents (e.g., pregelatinized maize starch,polyvinylpyrrolidone or hydroxypropyl methylcellulose); fillers (e.g.,lactose, microcrystalline cellulose or calcium phosphate); lubricants(e.g., magnesium stearate, talc or silica); disintegrants (e.g., potatostarch or sodium starch glycolate); or wetting agents (e.g., sodiumlauryl sulphate). In an embodiment, the tablets are coated by methodswell known in the art. In the case of tablets, capsules, caplets,pellets or granules for oral administration, pH sensitive entericcoatings, such as Eudragits™, designed to control the release of activeingredients are optionally used. Oral dosage forms also include modifiedrelease, for example immediate release and timed-release, formulations.Examples of modified-release formulations include, for example,sustained-release (SR), extended-release (ER, XR, or XL), time-releaseor timed-release, controlled-release (CR), or continuous-release (CR orContin), employed, for example, in the form of a coated tablet, anosmotic delivery device, a coated capsule, a microencapsulatedmicrosphere, an agglomerated particle, e.g., as of molecular sievingtype particles, or, a fine hollow permeable fiber bundle, or choppedhollow permeable fibers, agglomerated or held in a fibrous packet.Timed-release compositions are formulated, for e.g. in liposomes orthose wherein the active compound is protected with differentiallydegradable coatings, such as by microencapsulation, multiple coatings,etc. Liposome delivery systems include, for example, small unilamellarvesicles, large unilamellar vesicles and multilamellar vesicles. In anembodiment, liposomes are formed from a variety of phospholipids, suchas cholesterol, stearylamine or phosphatidylcholines. For oraladministration in a capsule form, useful carriers or diluents includelactose and dried corn starch.

Liquid preparations for oral administration take the form of, forexample, solutions, syrups or suspensions, or they are suitablypresented as a dry product for constitution with water or other suitablevehicle before use. When aqueous suspensions and/or emulsions areadministered orally, the compound of the application is suitablysuspended or dissolved in an oily phase that is combined withemulsifying and/or suspending agents. If desired, certain sweeteningand/or flavoring and/or coloring agents are added. Such liquidpreparations for oral administration are prepared by conventional meanswith pharmaceutically acceptable additives such as suspending agents(e.g., sorbitol syrup, methyl cellulose or hydrogenated edible fats);emulsifying agents (e.g., lecithin or acacia); non-aqueous vehicles(e.g., almond oil, oily esters or ethyl alcohol); and/or preservatives(e.g., methyl or propyl p-hydroxybenzoates or sorbic acid). Usefuldiluents include lactose and/or high molecular weight polyethyleneglycols.

It is also possible to freeze-dry the compounds of the application anduse the lyophilizates obtained, for example, for the preparation ofproducts for injection.

In a further embodiment, a compound of the application is administeredparenterally. For example, solutions of a compound of the applicationare prepared in water suitably mixed with a surfactant such ashydroxypropylcellulose. Dispersions are also prepared in glycerol,liquid polyethylene glycols, DMSO and mixtures thereof with or withoutalcohol, and in oils. Under ordinary conditions of storage and use,these preparations contain a preservative to prevent the growth ofmicroorganisms. A person skilled in the art would know how to preparesuitable formulations. For parenteral administration, sterile solutionsof the compounds of the application are usually prepared, and the pH'sof the solutions are suitably adjusted and buffered. For intravenoususe, the total concentration of solutes should be controlled to renderthe preparation isotonic. For ocular administration, ointments ordroppable liquids are, for example, delivered by ocular delivery systemsknown to the art such as applicators or eye droppers. In an embodiment,such compositions include mucomimetics such as hyaluronic acid,chondroitin sulfate, hydroxypropyl methylcellulose and/or polyvinylalcohol, preservatives such as sorbic acid, EDTA and/or benzyl chromiumchloride, and the usual quantities of diluents or carriers. Forpulmonary administration, diluents and/or carriers will be selected tobe appropriate to allow the formation of an aerosol.

In a further embodiment, the compounds of the application are formulatedfor parenteral administration by injection, including using conventionalcatheterization techniques or infusion. Formulations for injection are,for example, presented in unit dosage form, e.g., in ampoules or inmulti-dose containers, with an added preservative. In an embodiment, thecompositions take such forms as sterile suspensions, solutions oremulsions in oily or aqueous vehicles, and, optionally containformulating agents such as suspending, stabilizing and/or dispersingagents. In all cases, the form must be sterile and must be fluid to theextent that easy syringability exists. Alternatively, the compounds ofthe application are suitably in a sterile powder form for reconstitutionwith a suitable vehicle, e.g., sterile pyrogen-free water, before use.

In an embodiment, compositions for nasal administration are convenientlyformulated as aerosols, drops, gels and powders. For intranasaladministration or administration by inhalation, the compounds of theapplication are conveniently delivered in the form of a solution, drypowder formulation or suspension from a pump spray container that issqueezed or pumped by the patient or as an aerosol spray presentationfrom a pressurized container or a nebulizer. Aerosol formulationstypically comprise a solution or fine suspension of the active substancein a physiologically acceptable aqueous or non-aqueous solvent and areusually presented in single or multidose quantities in sterile form in asealed container, which can take the form of a cartridge or refill foruse with an atomising device. Alternatively, the sealed container is aunitary dispensing device such as a single dose nasal inhaler or anaerosol dispenser fitted with a metering valve which is intended fordisposal after use. Where the dosage form comprises an aerosoldispenser, it will contain a propellant which is, for example, acompressed gas such as compressed air or an organic propellant such asfluorochlorohydrocarbon. Suitable propellants include but are notlimited to dichlorodifluoromethane, trichlorofluoromethane,dichlorotetrafluoroethane, heptafluoroalkanes, carbon dioxide or anothersuitable gas. In the case of a pressurized aerosol, the dosage unit issuitably determined by providing a valve to deliver a metered amount. Inan embodiment, the pressurized container or nebulizer contains asolution or suspension of the active compound. Capsules and cartridges(made, for example, from gelatin) for use in an inhaler or insufflatorare, for example, formulated containing a powder mix of a compound ofthe application and a suitable powder base such as lactose or starch. Inan embodiment, the aerosol dosage forms also take the form of apump-atomizer.

Compositions suitable for buccal or sublingual administration includetablets, lozenges, and pastilles, wherein the active ingredient isformulated with a carrier such as sugar, acacia, tragacanth, and/orgelatin and glycerine. Compositions for rectal administration areconveniently in the form of suppositories containing a conventionalsuppository base such as cocoa butter.

Suppository forms of the compounds of the application are useful forvaginal, urethral and rectal administrations. Such suppositories willgenerally be constructed of a mixture of substances that is solid atroom temperature but melts at body temperature. The substances commonlyused to create such vehicles include but are not limited to theobromaoil (also known as cocoa butter), glycerinated gelatin, otherglycerides, hydrogenated vegetable oils, mixtures of polyethyleneglycols of various molecular weights and/or fatty acid esters ofpolyethylene glycol. See, for example: Remington's PharmaceuticalSciences, 16th Ed., Mack Publishing, Easton, Pa., 1980, pp. 1530-1533for further discussion of suppository dosage forms.

In an embodiment, compounds of the application are coupled with solublepolymers as targetable drug carriers. Such polymers include, forexample, polyvinylpyrrolidone, pyran copolymer,polyhydroxypropylmethacrylamide-phenol,polyhydroxy-ethylaspartamide-phenol, or polyethyleneoxide-polylysinesubstituted with palmitoyl residues. In a further embodiment, compoundsof the application are coupled to a class of biodegradable polymersuseful in achieving controlled release of a drug, for example,polylactic acid, polyglycolic acid, copolymers of polylactic andpolyglycolic acid, polyepsilon caprolactone, polyhydroxy butyric acid,polyorthoesters, polyacetals, polydihydropyrans, polycyanoacrylates andcrosslinked or amphipathic block copolymers of hydrogels.

The compounds of the application including pharmaceutically acceptablesalts, solvates and prodrugs thereof are suitably used on their own butwill generally be administered in the form of a pharmaceuticalcomposition in which the one or more compounds of the application (theactive ingredient) is in association with a pharmaceutically acceptablecarrier. Depending on the mode of administration, the pharmaceuticalcomposition will comprise from about 0.05 wt % to about 99 wt % or about0.10 wt % to about 70 wt %, of the active ingredient, and from about 1wt % to about 99.95 wt % or about 30 wt % to about 99.90 wt % of apharmaceutically acceptable carrier, all percentages by weight beingbased on the total composition.

Compounds of the application are used alone or in combination with otherknown agents useful for treating diseases, disorders or conditionsmediated by proteasome inhibition. When used in combination with otheragents useful in treating diseases, disorders or conditions mediated byproteasome inhibition, it is an embodiment that the compounds of theapplication are administered contemporaneously with those agents. Asused herein, “contemporaneous administration” of two substances to asubject means providing each of the two substances so that they are bothbiologically active in the individual at the same time. The exactdetails of the administration will depend on the pharmacokinetics of thetwo substances in the presence of each other, and can includeadministering the two substances within a few hours of each other, oreven administering one substance within 24 hours of administration ofthe other, if the pharmacokinetics are suitable. Design of suitabledosing regimens is routine for one skilled in the art. In particularembodiments, two substances will be administered substantiallysimultaneously, i.e., within minutes of each other, or in a singlecomposition that contains both substances. It is a further embodiment ofthe present application that a combination of agents is administered toa subject in a non-contemporaneous fashion. In an embodiment, a compoundof the present application is administered with another therapeuticagent simultaneously or sequentially in separate unit dosage forms ortogether in a single unit dosage form. Accordingly, the presentapplication provides a single unit dosage form comprising a compound ofFormula I, an additional therapeutic agent, and a pharmaceuticallyacceptable carrier.

The dosage of compounds of the application varies depending on manyfactors such as the pharmacodynamic properties of the compound, the modeof administration, the age, health and weight of the recipient, thenature and extent of the symptoms, the frequency of the treatment andthe type of concurrent treatment, if any, and the clearance rate of thecompound in the subject to be treated. One of skill in the art candetermine the appropriate dosage based on the above factors. In anembodiment, compounds of the application are administered initially in asuitable dosage that is optionally adjusted as required, depending onthe clinical response. Dosages will generally be selected to maintain aserum level of compounds of the application from about 0.01 μg/cc toabout 1000 μg/cc, or about 0.1 μg/cc to about 100 μg/cc. As arepresentative example, oral dosages of one or more compounds of theapplication will range between about 1 mg per day to about 1000 mg perday for an adult, suitably about 1 mg per day to about 500 mg per day,more suitably about 1 mg per day to about 200 mg per day. For parenteraladministration, a representative amount is from about 0.001 mg/kg toabout 10 mg/kg, about 0.01 mg/kg to about 10 mg/kg, about 0.01 mg/kg toabout 1 mg/kg or about 0.1 mg/kg to about 1 mg/kg. For oraladministration, a representative amount is from about 0.001 mg/kg toabout 10 mg/kg, about 0.1 mg/kg to about 10 mg/kg, about 0.01 mg/kg toabout 1 mg/kg or about 0.1 mg/kg to about 1 mg/kg. For administration insuppository form, a representative amount is from about 0.1 mg/kg toabout 10 mg/kg or about 0.1 mg/kg to about 1 mg/kg. In an embodiment ofthe application, compositions are formulated for oral administration andthe compounds are suitably in the form of tablets containing 0.25, 0.5,0.75, 1.0, 5.0, 10.0, 20.0, 25.0, 30.0, 40.0, 50.0, 60.0, 70.0, 75.0,80.0, 90.0, 100.0, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600,650, 700, 750, 800, 850, 900, 950 or 1000 mg of active ingredient pertablet. In an embodiment, compounds of the application are administeredin a single daily dose or the total daily dose is divided into two,three, four or more daily doses.

V. Methods and Uses of the Application

The compounds of the application have been shown to be capable ofinhibiting proteasome activity.

Accordingly, the present application includes a method for inhibitingproteasome in a cell, either in a biological sample or in a patient,comprising administering an effective amount of one or more compounds ofthe application to the cell. The application also includes a use of oneor more compounds of the application for inhibition of proteasome in acell as well as a use of one or more compounds of the application forthe preparation of a medicament for inhibition of proteasome in a cell.The application further includes one or more compounds of theapplication for use in inhibiting proteasome in a cell.

As the compounds of the application have been shown to be capable ofinhibiting proteasome activity, the compounds of the application areuseful for treating diseases, disorders or conditions mediated byproteasome inhibition. Therefore the compounds of the presentapplication are useful as medicaments. Accordingly, the presentapplication includes a compound of the application for use as amedicament.

The present application also includes a method of treating a disease,disorder or condition that is mediated by proteasome inhibitioncomprising administering a therapeutically effective amount of one ormore compounds of the application to a subject in need thereof.

The present application also includes a use of one or more compounds ofthe application for treatment of a disease, disorder or conditionmediated by proteasome inhibition as well as a use of one or morecompounds of the application for the preparation of a medicament fortreatment of a disease, disorder or condition mediated by proteasomeinhibition. The application further includes one or more compounds ofthe application for use in treating a disease, disorder or conditionmediated by proteasome inhibition.

In an embodiment, the disease, disorder or condition mediated byproteasome inhibition is a neoplastic disorder. Accordingly, the presentapplication also includes a method of treating a neoplastic disordercomprising administering a therapeutically effective amount of one ormore compounds of the application to a subject in need thereof. Thepresent application also includes a use of one or more compounds of theapplication for treatment of a neoplastic disorder as well as a use ofone or more compounds of the application for the preparation of amedicament for treatment of a neoplastic disorder. The applicationfurther includes one or more compounds of the application for use intreating a neoplastic disorder. In an embodiment, the treatment is in anamount effective to ameliorate at least one symptom of the neoplasticdisorder, for example, reduced cell proliferation or reduced tumor mass,among others, in a subject in need of such treatment.

Compounds of the application have been demonstrated to be effectiveagainst the cell lines of a 60 human tumor cell line panel. Therefore inanother embodiment of the present application, the disease, disorder orcondition mediated by proteasome inhibition is cancer. Accordingly, thepresent application also includes a method of treating cancer comprisingadministering a therapeutically effective amount of one or morecompounds of the application to a subject in need thereof. The presentapplication also includes a use of one or more compounds of theapplication for treatment of cancer as well as a use of one or morecompounds of the application for the preparation of a medicament fortreatment of cancer. The application further includes one or morecompounds of the application for use in treating cancer. In anembodiment, the compound is administered for the prevention of cancer ina subject such as a mammal having a predisposition for cancer.

In an embodiment, the cancer is selected from a cancer of the skin,blood, prostate, colorectum, pancreas, kidney, ovary, breast, forexample mammary, liver, tongue and lung. In another embodiment, thecancer is selected from leukaemia, lymphoma, non-Hodgkin's lymphoma andmultiple myeloma. In a further embodiment of the present application,the cancer is selected from leukemia, melanoma, lung cancer, coloncancer, brain cancer, ovarian cancer, breast cancer, prostate cancer andkidney cancer.

In an embodiment, the disease, disorder or condition mediated byproteasome inhibition is a disease, disorder or condition associatedwith an uncontrolled and/or abnormal cellular activity affected directlyor indirectly by proteasome inhibition. In another embodiment, theuncontrolled and/or abnormal cellular activity that is affected directlyor indirectly by proteasome inhibition is proliferative activity in acell. Accordingly, the application also includes a method of inhibitingproliferative activity in a cell, comprising administering an effectiveamount of one or more compounds of the application to the cell. Thepresent application also includes a use of one or more compounds of theapplication for inhibition of proliferative activity in a cell as wellas a use of one or more compounds of the application for the preparationof a medicament for inhibition of proliferative activity in a cell. Theapplication further includes one or more compounds of the applicationfor use in inhibiting proliferative activity in a cell.

The present application also includes a method of inhibitinguncontrolled and/or abnormal cellular activities affected directly orindirectly by proteasome inhibition in a cell, either in a biologicalsample or in a subject, comprising administering an effective amount ofone or more compounds of the application to the cell. The applicationalso includes a use of one or more compounds of the application forinhibition of uncontrolled and/or abnormal cellular activities affecteddirectly or indirectly by proteasome inhibition in a cell as well as ause of one or more compounds of the application for the preparation of amedicament for inhibition of uncontrolled and/or abnormal cellularactivities affected directly or indirectly by proteasome inhibition in acell. The application further includes one or more compounds of theapplication for use in inhibiting uncontrolled and/or abnormal cellularactivities affected directly or indirectly by proteasome inhibition in acell.

The administration of the compound of Example 1 of the presentapplication in combination with either bortezomib or dexamethasone hasbeen demonstrated herein to be capable of being synergistic.Accordingly, the present application also includes a method of treatinga disease, disorder or condition that is mediated by proteasomeinhibition comprising administering a therapeutically effective amountof one or more compounds of the application in combination with anotherknown agent useful for treatment of a disease, disorder or conditionmediated by proteasome inhibition to a subject in need thereof. Thepresent application also includes a use of one or more compounds of theapplication in combination with another known agent useful for treatmentof a disease, disorder or condition mediated by proteasome inhibitionfor treatment of a disease, disorder or condition mediated by proteasomeinhibition as well as a use of one or more compounds of the applicationin combination with another known agent useful for treatment of adisease, disorder or condition mediated by proteasome inhibition for thepreparation of a medicament for treatment of a disease, disorder orcondition mediated by proteasome inhibition. The application furtherincludes one or more compounds of the application in combination withanother known agent useful for treatment of a disease, disorder orcondition mediated by proteasome inhibition for use in treating adisease, disorder or condition mediated by proteasome inhibition. In anembodiment, the disease, disorder or condition mediated by proteasomeinhibition is cancer such as multiple myeloma. In another embodiment,the other known agent useful for treatment of a disease, disorder orcondition mediated by proteasome inhibition is bortezomib ordexamethasone.

In a further embodiment, the disease, disorder or condition mediated byproteasome inhibition is cancer and the one or more compounds of theapplication are administered in combination with one or more additionalcancer treatments. In another embodiment, the additional cancertreatment is selected from radiotherapy, chemotherapy, targetedtherapies such as antibody therapies and small molecule therapies suchas tyrosine-kinase inhibitors, immunotherapy, hormonal therapy andanti-angiogenic therapies.

The present application also includes a method of inhibiting thedegradation of a protein by a proteasome capable of degrading theprotein, comprising contacting the proteasome with an effective amountof one or more compounds of the application. The present applicationfurther includes a use of one or more compounds of the application forinhibition of the degradation of a protein by a proteasome capable ofdegrading the protein as well as a use of one or more compounds of theapplication for preparation of a medicament for inhibition of thedegradation of a protein by a proteasome capable of degrading theprotein. The present application also includes one or more compounds ofthe application for inhibiting the degradation of a protein by aproteasome capable of degrading the protein.

In an embodiment, the protein is marked with ubiquitin. In anotherembodiment, the protein is p53.

The present application also includes a method of treating acceleratedand/or enhanced proteolysis, comprising administering a therapeuticallyeffective amount of one or more compounds of the application to asubject in need thereof. The present application further includes a useof one or more compounds of the application for treatment of acceleratedand/or enhanced proteolysis as well as a use of one or more compounds ofthe application for the preparation of a medicament for treatment ofaccelerated and/or enhanced proteolysis. The present application alsoincludes one or more compounds of the application for treatingaccelerated and/or enhanced proteolysis. In an embodiment, the subjectis a mammal having or predisposed to accelerated and/or enhancedproteolysis.

In another embodiment of the present application, the disease, disorderor condition mediated by proteasome inhibition is selected from adisease, disorder or condition associated with the cell cycle,Endoplasmic Reticulum Associated Protein Degradation, transcriptionfactor regulation, gene expression, cell differentiation, the immuneresponse, angiogenesis and the regulation or induction of apoptosis.

In another embodiment of the present application, the disease, disorderor condition mediated by proteasome inhibition is selected from viralinfection, an inflammatory disease, an autoimmune disease, heartdisease, an age-related eye disease and a neurodegenerative disease

In another embodiment of the present application, the disease, disorderor condition mediated by proteasome inhibition is selected from HIVinfection, type-1 diabetes, type-2 diabetes, allergic reactions, asthma,inflammatory arthritis, rheumatoid arthritis, osteoporosis,osteoarthritis, psoriasis, seronegative spondyloarthopathies, ankylosingspondylitis, systemic lupus erythematosus (SLE), autoimmune thyroiddisease, congestive heart failure, pressure-overload cardiachypertrophy, viral myocarditis, myocardial ischemic injury, heartdisease, artherogenesis, atherosclerosis, cardiac events in diabetes,vascular disorders in diabetes, muscle wasting, obesity, Alzheimer'sdisease, Parkinson's disease, Huntington's disease, amyotrophic lateralsclerosis, autoimmune thyroid disease, cachexia, Crohn's disease,inflammatory bowel disease, sepsis, hepatitis B, transplantationrejection and related immunology, retina degeneration, cataracts andglaucoma.

In a further embodiment, the compounds of the application are used fortreating a disease or disorder associated with inflammation in humans aswell as other mammals. Exemplary inflammatory conditions include, butnot limited to rheumatoid, arthritis, multiple sclerosis, degenerativejoint disease, spondouloarthropathies, osteoporosis, diabetes,Alzheimer's disease, Parkinson's disease, shock, among others.

In a further embodiment, the compounds of the application are used fortreating a disease or disorder selected from allergies and respiratoryconditions, including asthma, bronchitis, pulmonary fibrosis, allergicrhinitis, oxygen toxicity, emphysema, chronic bronchitis, acuterespiratory distress syndrome, and any chronic obstructive pulmonarydisease (COPD).

In a further embodiment, the compounds of the application are used fortreating a disease or disorder selected from viral infections (HIV-1 andHIV-2), osteoporosis, osteoarthritis, psoriasis, restenosis heartdisease, diabetes-associated cardiovascular disorders, inflammatorybowel disease, inflammatory and autoimmune diseases (arthritis,psoriasis), seronegative spondyloarthropathies (SpA), muscle wasting,obesity, allergy and asthma, neurodegenerative disorders, includingAlzheimer's (AD) and Parkinson's (PD) diseases, and autoimmune diseasesin a mammal having or predisposed to said disease or disorder.

The introduction of a halogen atom into a molecule also provides theopportunity for the use of the molecule in radiolabeling applications.For example, ¹⁸F is used as a radiolabel tracer in the sensitivetechnique of Positron Emission Tomography (PET). Accordingly the presentapplication also includes methods of using the compounds of Formula Ifor diagnostic and imaging purposes, wherein the compounds of Formula Icomprise at least one radiolabel, such as ¹⁸F.

Therefore the present application includes the use of one of morecompounds of the application for radiolabel imaging, wherein thecompounds of the application comprise at least one radiolabel, such as¹⁸F.

The present application also includes a method of radiolabel imagingcomprising contacting a subject to be imaged with one or more compoundsof the application, and performing an imaging technique on the subject,wherein the compounds of the application comprise at least oneradiolabel, such as ¹⁸F. In an embodiment the subject is a human oranimal and the imaging technique is PET and the one or more compounds ofthe application or contacted with the subject by administration of aimaging effective amount of the compound(s) to the subject.

The following non-limiting examples are illustrative of the presentapplication:

EXAMPLES

The introduction of the fluorine atom into molecules may bring aboutchanges in the physical and/or chemical properties of the parentmolecules, for example it may result in the enhancement ofpharmacokinetic properties and/or biological activities. Replacement ofhydrogen atoms may also result in improved thermal and metabolicstability. Improved metabolic stability is generally a desirable featuresince the possibility exists that in vivo decomposition may producetoxic effects. The properties of the fluorine atom include its smallsize, low polarizability, high electronegativity and its ability to formstrong bonds with carbon. Accordingly, bioactive compounds containingfluorinated groups such as —OCHF₂ are useful.

The geminal combination of an alkoxy or aryloxy group with a fluorineatom offers the possibility of bonding/nonbonding resonance, which canbe formally expressed by the superposition of a covalent and ioniclimiting structure. This phenomenon, which reveals itself as alengthening and weakening of the carbon-halogen bond and a shorteningand strengthening of the carbon-oxygen bond is known as the generalizedanomeric effect [Schlosser et al. Chem. Rev. 2005, 105, 827-856].

A. General Methods

All starting materials used herein were commercially available orearlier described in the literature. The ¹H and ¹³C NMR spectra wererecorded either on Bruker 300, Bruker DPX400 or Varian +400spectrometers operating at 300, 400 and 400 MHz for ¹H NMR respectively,using TMS or the residual solvent signal as an internal reference, indeuterated chloroform as solvent unless otherwise indicated. Allreported chemical shifts are in ppm on the delta-scale, and the finesplitting of the signals as appearing in the recordings is generallyindicated, for example as s: singlet, br s: broad singlet, d: doublet,t: triplet, q: quartet, m: multiplet. Unless otherwise indicated, in thetables below, ¹H NMR data was obtained at 400 MHz, using CDCl₃ as thesolvent.

Purification of products was carried out using Chem Elut ExtractionColumns (Varian, cat #1219-8002), Mega BE-SI (Bond Elut Silica) SPEColumns (Varian, cat #12256018; 12256026; 12256034) or by flashchromatography in silica-filled glass columns.

B: Synthesis and Characterization of Compounds I. Preparation ofIntermediate Compounds of Formula II

Scheme V outlines the synthesis of intermediate compounds of FormulaIV(a) and Formula V(a) used in the preparation of the intermediatecompound of Formula II(a)(i), used in the preparation of compounds ofFormula I wherein R₂ and/or R₃ are a —CH₂—O—CHF₂ moiety.

Reagents and conditions used in Scheme V: (i)2-fluorosulfonyldifluoroacetic acid, Cu(I)I, Na₂SO₄, CH₃CN 0° C./30 min;(ii) H₂, Pd/C (10%), THF, RT/2 hrs; (iii) 2M HCl/Et₂O, 0° C. to RT/2hrs.

(a) Preparation of(S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionic acid benzylester (XIII(a))

To a stirred solution of the compound of Formula XII(a), benzyl2-(tert-butoxycarbonylamino)-3-hydroxypropanoate (1 g, 3.38 mmol) inacetonitrile (10 mL) was added copper(I) iodide (64.4 mg, 0.338 mmol)and sodium sulfate (48.1 mg, 0.338 mmol). The resulting mixture wasstirred at 60° C. and treated with 2,2-difluoro-2-fluorosulfonylaceticacid (524 μL, 5.08 mmol), dropwise, as a solution in acetonitrile (2 mL)over a period of 1.5 h. Upon completion of the addition, the mixture wasstirred for a further 30 min then cooled to room temperature. Themixture was diluted with diethyl ether and washed with brine (2×), water(3×) and brine (lx). The organic phase was dried, filtered andconcentrated in vacuo then chromatographed in 0-30% ethyl acetate inhexanes, to provide the compound of Formula XIII(a),(S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionic acid benzylester (458 mg, 40%) as a colorless sticky oil. ¹H NMR (300 MHz, CDCl₃):δ (ppm) 7.32-7.38 (m, 5H), 6.18 (wt, 1H), 5.28 (dd, 1H), 5.19 (dd, 2H),4.55 (dt, 1H) 4.22 (td, 1H), 4.15 (m, 2H), 1.38 (s, 9H).

Alternatively, the compound of Formula XIII(a),(S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionic acid benzylester was prepared by difluoromethyl insertion of(S)-2-tert-butoxycarbonylamino-3-thioformyloxy-propionic acid benzylester in a 40-90% yield using 2,2-difluoro-1,3-dimethylimidazolidine, asa reagent for difluoromethyl insertion.

(b) Preparation of(S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionic acid (IV(a))

A solution of the compound of Formula XIII(a),(S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionic acid benzylester (1.76 g, 5.09 mmol) in THF was stirred with 10% Pd/C (360 mg)under a hydrogen atmosphere for 2 hours. The reaction mixture wasfiltered and concentrated to give the compound of Formula IV(a),(S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionic acid (1.3 g,100%) as a sticky, colorless oil. ¹H NMR (300 MHz, CDCl₃): δ (ppm) 6.21(wt, 1H), 5.35 (d, 1H), 4.59 (m, 1H), 4.35 (m, 1H), 4.21 (m, 1H) and1.42 (s, 9H).

(c) Preparation of (S)-2-amino-3-difluoromethoxy-propionic acid benzylester Hydrochloride salt (V(a))

A solution of the compound of Formula XIII(a),(S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionic acid benzylester (2.11 g, 5.89 mmol) in ether (10 mL) was treated with 2MHCl/ether, and stirred at 0° C. for 2 hours. The reaction mixture wasconcentrated to dryness and triturated with hexane/ether to give thecompound of Formula V(a) (S)-2-amino-3-difluoromethoxy-propionic acidbenzyl ester hydrochloride salt (1.15 g, 69%) as a white powder. ¹H NMR(300 MHz, CDCl₃): b (ppm) 7.40-7.33 (m, 5H), 6.53 (broad s, 1H), 6.18(wt, 1H), 5.25 (dd, 1H), 5.21 (dd, 2H), 4.53 (dt, 1H) 4.18 (td, 1H),4.16-4.13 (m, 2H).

Scheme VI outlines the synthesis of intermediate compounds of FormulaIII(a)(i) used in the preparation of the compounds of Formula I whereinR₂ and R₃ are a —CH₂—O—CHF₂ moiety.

Reagents and conditions used in Scheme VI: (i) EDCl.HCl, HOBt,N-methylmorpholine, CH₂Cl₂, 0° C./ON; (ii) H₂, Pd/C (10%), THF, RT/1hrs.

(d) Preparation of(S)-2-((S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionylamino)-3-difluoromethoxy-propionicacid benzyl ester (II(a)(ii))

To a solution of the compound of Formula IV(a),(S)-2-tert-butoxycarbonylamino-3-difluoromethoxypropionic acid (1.15 g,4.49 mmol) and the compound of Formula V(a),(S)-2-amino-3-difluoromethoxypropionic acid benzyl ester hydrochloridesalt (1.15 g, 4.08 mmol), HOBt (0.689 g, 5.10 mmol) and EDCl.HCl (0.867g, 5.10 mmol) in dichloromethane (20 mL) was added N-methylmorpholine(0.45 mL, 8.16 mmol) dropwise at 0° C. The reaction mixture was allowedto warm up to room temperature and stirred overnight. The mixture wasthen diluted with ethyl acetate and washed successively with water, 1NHCl and brine. The organic layer was dried over MgSO₄ and concentrated.The crude product was purified by silica-gel column chromatography,eluting with 10% to 12.5% ethyl acetate in hexanes, to give the compoundof Formula II(a)(ii),(S)-2-((S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionylamino)-3-di-fluoromethoxy-propionicacid benzyl ester (1.29 g, 65%) as an off-white solid. ¹H NMR (300 MHz,CDCl₃): δ (ppm) 7.35-7.41 (m, 5H), 7.18 (td, 1H), 6.18 (wt, 1H), 6.22(wt, 1H), 5.25-5.20 (m, 1H), 5.19 (s, 2H), 4.82 (td, 1H), 4.42 (br s,1H), 4.31 (td, 1H), 4.20-4.15 (m, 2H), 4.01 (dd, 1H), 1.41 (s, 9H).

In a similar manner, using the above general procedure, the intermediatecompounds shown in Table 1 were synthesized.

(e) Preparation of(S)-2-((S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionylamino)-3-difluoromethoxy-propionicacid (II(a)(i))

A solution of the compound of Formula II(a)(ii),(S)-2-((S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionylamino)-3-difluoromethoxypropionicacid benzyl ester (1.27 g, 2.63 mmol) in THF was stirred with 10% Pd/C(400 mg) under a hydrogen atmosphere for 1 hour. The reaction mixturewas filtered and concentrated to give the compound of Formula II(a)(i),(S)-2-((S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionylamino)-3-difluoromethoxy-propionicacid (1.03 g, ˜100%) as a sticky, off-white foam. NMR (d₆-DMSO, 400 MHz)δ (ppm) 8.34 (d, J=8 Hz, 1H), 7.12 (d, J=8 Hz, 1H), 6.66 (t, J=76 Hz,1H), 6.62 (t, J=76 Hz, 1H), 4.57-4.51 (m, 1H), 4.37-4.29 (m, 1H),4.15-4.09 (m, 1H), 4.04-3.97 (m, 2H), 3.92-3.83 (m, 1H), 1.37 (s, 9H).Scheme VII outlines the synthesis of compound intermediates of FormulaIV(b) and Formula V(b) which are used in the preparation of thecompounds of Formula (I) wherein R₂ and/or R₃ is a —CH₂—O—CH₃ moiety.

Reagents and conditions used in Scheme VII: (i) BF₄(OMe)₃, protonsponge, CH₂Cl₂, 0° C. to TR/ON; (ii) TFA, CH₂Cl₂, 0° C./30 min; (iii)HCl/Et₂O.

(a) Preparation of (S)-2-tert-butoxycarbonylamino-3-methoxy-propionicacid benzyl ester (XIII(b))

To a solution of the compound of Formula XII(a),(S)-2-tert-butoxycarbonylamino-3-hydroxy-propionic acid benzyl ester(1.7 g, 5.76 mmol) in dichloromethane (50 mL) was added trimethyloxoniumtetrafluoroborate (1.11 g, 7.50 mmol), followed by the portion-wiseaddition of proton sponge (1.61 g, 7.50 mmol). After stirring for 24 hrsat RT, the solution was concentrated, and the residue was dissolved inethyl acetate, and the solution filtered through a pad of celite. Thefiltrate was washed with 1 M HCl and brine. The organic layers weredried over MgSO₄, filtered, and concentrated in vacuo. Silica-gel flashchromatography with 5% to 15% ethyl acetate in hexanes afforded thecompound of Formula XIII(b),(S)-2-tert-butoxycarbonylamino-3-methoxy-propionic acid benzyl ester(1.24 g, 69.6%) as a colorless oil. ¹H NMR (300 MHz, CDCl₃): δ (ppm)7.35-7.29 (m, 5H), 4.90-4.87 (m, 1H), 4.51 (s, 2H), 3.92-3.87 (m, 1H),3.80-3.78 (m, 1H), 3.56 (dd, 2H), 3.42 (dd, 1H), 3.33 (s, 3H), 1.42 (s,9H).

(b) Preparation of (S)-2-tert-butoxycarbonylamino-3-methoxy-propionicacid (IV(b))

The compound of Formula IV(b) was prepared in a similar manner as thecompound of Formula IV(a), described above, from the compound of FormulaXIII(b) (S)-2-tert-butoxycarbonylamino-3-methoxy-propionic acid benzylester (0.76 g, 2.46 mmol), to provide the compound of Formula IV(b),(S)-2-tert-butoxycarbonylamino-3-methoxy-propionic acid (0.540 mg, 100%)as a sticky, colorless oil.

(c) Preparation of (S)-2-amino-3-methoxy-propionic acid benzyl ester,hydrochloride salt (V(b))

The compound of Formula V(b) was prepared, as a hydrochloride salt, in asimilar manner as the compound of Formula V(a), described above, fromthe compound of Formula XIII(b),(S)-2-tert-butoxycarbonylamino-3-methoxy-propionic acid benzyl ester(0.80 g, 2.59 mmol), to provide the compound of Formula V(b),(S)-2-amino-3-methoxy-propionic acid benzyl ester, hydrochloride salt(100%) as a white powder.

Scheme VIII outlines the synthesis of the intermediate compound ofFormula II(b)(i) which is used in the preparation of the compounds ofFormula (I) wherein R₂ is a —CH₂—O—CHF₂ moiety and R₃ is a —CH₂—O—CH₃group.

Reagents and conditions used in Scheme VIII: (i) EDCl.HCl, HOBt, DIPEA,CH₂Cl₂, 0° C./ON; (ii) H₂, Pd/C (10%), THF, RT/2 hrs.

(d) Preparation of(S)-2-((S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionylamino)-3-methoxy-propionicacid benzyl ester (II(b)(ii))

The compound of Formula II(b)(ii) was prepared as an off-white foam in asimilar manner as the compound of Formula II(a)(ii), described above,from the compound of Formula IV(a),(S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionic acid and thecompound of Formula V(b), (S)-2-amino-3-methoxy-propionic acid benzylester, hydrochloride salt.

(e) Preparation of(S)-2-((S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionylamino)-3-methoxy-propionicacid (II(b)(i))

The compound of Formula II(b)(i) was prepared, as an off-white stickyfoam, in a similar manner as the compound of Formula II(a)(i), describedabove from the compound of Formula II(b)(ii),(S)-2-((S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionylamino)-3-methoxy-propionicacid benzyl ester.

Scheme IX outlines the synthesis of the intermediate of FormulaII(c)(i), used in the preparation of the compounds of Formula (I) whenR₂ is a —CH₂—O—CH₃ group and R₃ is a —CH₂—O—CHF₂ moiety.

Reagents and conditions used in Scheme IX: (i) EDCl.HCl, HOBt, DIPEA,CH₂Cl₂, 0° C./ON; (ii) H₂, Pd/C (10%), THF, RT/2 hrs.

In a similar manner to the above general procedure, the other compoundsshown in Table 2 were synthesized

II. Preparation of Intermediate Compounds of Formula III

Scheme X outlines the synthesis of intermediate epoxyketones of FormulaIII used for the preparation of compounds of Formula I wherein R⁴ is—CH₂C₆H₅ and R⁵ is methyl.

Reagents and conditions used in Scheme X: (i) iBuOCOCl,N-methylmorpholine, HNMe(OMe).HCl, TEA, CH₂Cl₂, 0° C./45 min; (ii)isopropenylmagnesium bromide, THF, 0° C./2 hrs or 2-bromopropene,t-BuLi, Et₂O, −78° C./2 hrs; (iii) (a) H₂O₂ (35%), benzonitrile,iPr₂EtN, MeOH, 0° C. to RT/ON; (b) Silica-gel column chromatography;(iv) TFA, CH₂Cl₂, 0° C./30 min.

In a similar manner as Scheme X, the synthesis of the intermediateepoxyketones of Formula III(b) for compounds of Formula I wherein R₄ isCH₂CH(CH₃)₂ and R₅ is methyl was prepared.

(a) Preparation of[(S)-1-(methoxy-methyl-carbamoyl)-2-phenyl-ethyl]-carbamic acidtert-butyl ester (VII(a))

To a solution of (S)-2-tert-butoxycarbonylamino-3-phenyl-propionic acid(24.85 g, 93.66 mmol) in dichloromethane (150 mL) was addedN-methylmorpholine (10.3 mL, 93.66 mmol), followed by addition ofisobutyl chloroformate (12.25 mL, 93.66 mmol) at 0° C. The reactionmixture was stirred for 20 min. then N,O-dimethylhydroxylaminehydrochloride (9.14 g, 93.66 mmol) in one portion was added.Subsequently, triethylamine (13 mL, 93.66 mmol) was added dropwise over15 min. The reaction mixture was stirred for another hour, then it wasquenched with 1N HCl (100 mL) and the organic phase was washed withsaturated NaHCO₃ and brine (500 mL). The organic layers were dried over(MgSO₄), filtered, and concentrated in vacuo to give the Weinreb amideof Formula VII(a),[(S)-1-(methoxy-methyl-carbamoyl)-2-phenyl-ethyl]-carbamic acidtert-butyl ester as a clear sticky oil (29.3 g, 100%). ¹H NMR (400 MHz,d₆-DMSO): δ (ppm) 7.33-7.09 (m, 6H), 4.61-4.47 (m, 1H), 3.70 (s, 3H),3.08 (s, 3H), 2.89-2.78 (m, 1H), 2.75-2.63 (m, 1H), 1.29 (s, 9H).

(b) Preparation of ((S)-1-benzyl-3-methyl-2-oxo-but-3-enyl)-carbamicacid tert-butyl ester (VIII(a))

To a 0° C. solution of the above Weinreb amide of Formula VII(a), (28.88g, 93.66 mmol) in THF (150 mL) was added a 0.5 M solution in THF ofisopropenyl magnesium bromide (386 mL, 192.9 mmol) at 0° C. over 40 min.The reaction mixture was then stirred at room temperature for 2 hours.The reaction mixture was then quenched at 0° C. with 1N HCl (350 mL).The aqueous layer was extracted with EtOAc (2×200 mL). The organic layerwas washed successively with water and brine, dried over MgSO₄,filtered, and concentrated in vacuo to give, after silica-gel flashchromatography with 5% to 10% ethylacetate/hexanes, the compound ofFormula VIII(a), (S)-1-benzyl-3-methyl-2-oxo-but-3-enyl)-carbamic acidtert-butyl ester (14.5 g, 53.5%) as a white powder. ¹H NMR (400 MHz,d₆-DMSO): δ (ppm) 7.33-7.09 (m, 6H), 4.61-4.47 (m, 1H), 3.70 (s, 3H),3.08 (s, 3H), 2.89-2.78 (m, 1H), 2.75-2.63 (m, 1H), 1.29 (s, 9H).

(c) Preparation of[(S)-1-benzyl-2-((S)-2-methyl-oxiranyl)-2-oxo-ethyl]-carbamic acidtert-butyl ester and[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethyl]-carbamic acidtert-butyl ester (IX(a))

To a solution of the above compound of Formula VIII(a),((S)-1-benzyl-3-methyl-2-oxo-but-3-enyl)-carbamic acid tert-butyl ester(5.78 g, 20 mmol) in MeOH (250 mL) at 0° C. was added benzonitrile(15.46 mL, 150 mmol), H₂O₂ 35% solution in water (34.4 mL, 400 mmol),and diisopropylethylamine (26 mL, 150 mmol). The reaction mixture wasstirred at 0° C. to room temperature overnight. The resulting mixturewas concentrated under reduced pressure to dryness. The obtained residuewas quenched with ice-water (100 mL) to provide a white precipitate.After filtration, the aqueous layer was extracted with 20% ethyl acetatein hexanes (2×200 mL). The organic layer was washed successively withwater and brine, dried over MgSO₄, filtered, and concentrated in vacuoto give, after silica-gel flash chromatography with 3% to 3.5% ethylacetate/hexanes the compound of Formula S,R-IX(a),[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethyl]-carbamic acidtert-butyl ester (3.33 g, 54%) as a white solid (¹H NMR (300 MHz,CDCl₃): δ (ppm) 7.21-7.29 (m, 3H), 7.17-7.21 (m, 2H), 4.92 (dd, 1H),4.58 (td, 1H), 3.25 (d, 1H), 3.18 (dd, 1H), 2.94 (d, 1H), 2.75 (dd, 1H),1.45 (s, 3H), 1.39 (s, 9H)), and the compound of Formula S,S-IX(a),[(S)-1-benzyl-2-((S)-2-methyl-oxiranyl)-2-oxo-ethyl]-carbamic acidtert-butyl ester (1.66 g, 27%) as a sticky oil (¹H NMR (300 MHz, CDCl₃):δ (ppm) 7.30-7.22 (m, 3H), 7.20-7.15 (m, 2H), 4.95 (dd, 1H), 4.62 (td,2H), 3.25 (d, 1H), 3.00 (dd, 1H), 2.82 (dd, 1H), 2.61 (dd, 2H), 1.45 (s,3H), 1.40 (s, 9H)).

Preparation of(S)-2-amino-1-((R)-2-methyl-oxiranyl)-3-phenyl-propan-1-one, TFA salt(S,R-III(a))

To a solution of (2.20 g, 7.20 mmol) of the compound of FormulaS,R-IX(a), [(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethyl]-carbamicacid tert-butyl ester in dichloromethane (10 mL), TFA (3.3 mL) was addedat 0° C. The reaction mixture was stirred for 30 min. Excess of TFA wasevaporated to dryness, and the residue obtained was triturated with 20%ether in hexanes (20 mL), followed by 100% hexanes. After evaporation ofsolvents, drying under high vacuum provided the compound of FormulaS,R-III(a) (S)-2-amino-1-((R)-2-methyl-oxiranyl)-3-phenyl-propan-1-one,TFA salt (2.3 g, 100%), as an off-white powder. ¹H NMR (300 MHz,methanol-d): δ(ppm) 7.22-7.44 (m, 5H), 4.32 (dd, 1H), 4.39 (dd, 1H),3.17 (dd, 1H), 2.95 (dd, 1H), 2.88 (dd, 1H), 1.57 (s, 3H).

Alternatively, epoxyketones of the Formulae S,S-III(a) and S,R-III(a)can be prepared as outlined in Schemes XI and XII.

Reagents and conditions used in Scheme XI: (i) NaBH₄, CeCl₃.7H₂O, MeOH,THF, 0° C./30 min; (ii) (a) VO(acac)₂, t-BuO₂H, CH₂Cl₂, 0° C. to RT/1hr; (b) silica-gel column chromatography; (iii) (a) Dess-Martinperiodinane, CH₂Cl₂, 0° C. to RT/2 hrs; (b) TFA, CH₂Cl₂, 0° C./30 min.

Reagents and conditions used in Scheme XII: (i) iBuOCOCl,N-methylmorpholine, HNMe(OMe).HCl, TEA, CH₂Cl₂, 0° C./1 hr.; (ii)isopropenylmagnesium bromide, THF, 0° C./2 hrs or 2-bromopropene,t-BuLi, Et₂O, −78° C./2 hrs.; (iii) (a) H₂O₂ (35%), benzonitrile,i-Pr₂EtN, MeOH, 0° C. to RT/ON; (b) silica-gel column chromatography;(iv) H₂, Pd/C (10%), TFA, RT/6 hrs.

II. Preparation of Compounds of Formula I Example 1

The preparation of the compound of Formula I of Example 1,2-methyl-thiazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amideis outlined in Scheme XIII.

Reagents and conditions used in Scheme XIII: (i) HBTU, HOBt, DIPEA, THF,0° C. to RT/ON; (ii) H₂, Pd/C (10%), THF, RT/2 hrs.; (iii) HBTU, HOBt,DIPEA, THF, 2-methyl-thiazole-5-carboxylic acid, 0° C. to RT/ON.

(a) Preparation of((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxy-ethylcarbamoyl}-2-difluoromethoxy-ethyl)-carbamicacid tert-butyl ester (XIV(a))

To a solution of the compound of Formula II(b)(i),(S)-2-((S)-2-tert-butoxycarbonylamino-3-difluoromethoxy-propionylamino)-3-methoxy-propionicacid (2.75 g, 7.028 mmol) and the compound of Formula S,R-III(a),(S)-2-amino-1-((R)-2-methyl-oxiranyl)-3-phenyl-propan-1-one, TFA salt(12.04 g, 6.389 mmol), HOBt (1.04 g, 7.67 mmol), HBTU (2.91 g 7.67,mmol) in THF (75 mL) was added DIPEA (2.22 mL, 12.75 mmol) dropwise at0° C. The reaction mixture was allowed to warm up to room temperatureand was stirred overnight. The mixture was then quenched with ice water,washed with NaHCO₃ and brine and extracted with 2×100 mL of ethylacetate. The organic layer was dried over MgSO₄ and concentrated. Thecrude product was purified by column chromatography, eluting with 20% to30% ethyl acetate in hexanes, to give the title compound (2.7 g, 73%) asan off-white solid. ¹H NMR (300 MHz, CDCl₃): δ (ppm) 7.21-7.32 (m, 3H),7.14 (dd, 2H), 6.85 (wd, 1H), 6.72 (wd, 1H), 6.18 (wt, 1H), 6.14 (wt,1H), 5.26 (br s, 1H), 4.86 (td, 1H), 4.58 (td, 1H), 4.36 (m, 1H),4.32-4.08 (m, 2H), 4.01 (dd, 1H), 3.90 (dd, 1H), 3.24 (d, 1H), 3.12 (dd,1H), 2.90 (d, 1H), 2.85 (dd, 1H), 1.48 (s, 3H), 1.44 (s, 9H).

In a similar manner to the above general procedure, the compounds shownin Table 3 were synthesized.

(b) Preparation of(S)-2-amino-N—{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxy-ethyl}-3-difluoromethoxy-propionamideTFA salt (XV(a))

To a solution of the compound of Formula XIV(a),((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxy-ethylcarbamoyl}-2-difluoromethoxy-ethyl)-carbamicacid tert-butyl ester (2.68 g, 4.62 mmol) in dichloromethane (10 mL) at0° C. was added TFA (10 mL), and the resulting mixture was stirred for 1hr. Excess TFA was evaporated to dryness, and the residue obtained wastriturated with ether in hexanes (2×20 mL) to provide the compound ofFormula XV(a),(S)-2-amino-N—{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxy-ethyl}-3-difluoromethoxy-propionamideTFA salt (2.34 g, 85%), as a pale-yellow solid. ¹H NMR (300 MHz,d₆-DMSO): δ (ppm) 7.42-7.32 (m, 3H), 7.23 (dd, 2H), 6.85 (wd, 1H), 6.71(br s, 1H), 6.68 (wd, 1H), 6.10 (w t, 1H), 5.98 (wt, 1H), 5.12 (br s,1H), 4.78 (td, 1H), 4.51 (td, 1H), 4.29 (m, 1H), 4.30-3.99 (m, 2H), 3.97(dd, 1H), 3.85 (dd, 1H), 3.21 (d, 1H), 3.10 (dd, 1H), 2.86 (d, 1H), 2.81(dd, 1H), 1.45 (s, 3H).

In a similar manner to the above general procedure, the compounds shownin Table 4 were synthesized.

(c) Preparation of 2-methyl-thiazole-5-carboxylicacid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxy-ethylcarbamoyl}-2-difluoromethoxy-ethyl)-amide(Example 1)

To a solution of the compound of Formula XV(a),(S)-2-amino-N—{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxy-ethyl}-3-difluoromethoxy-propionamideTFA salt (2.2 g, 3.70 mmol), 2-methyl-thiazole-5-carboxylic acid (0.635g, 4.44 mmol), HOBt (0.649 g, 4.81 mmol) and HBTU (1.82 g, 4.81 mmol) inTHF (70 mL) was added DIPEA (1.29 mL, 7.4 mmol) dropwise at 0° C. Thereaction mixture was allowed to warm up to room temperature and wasstirred overnight. The mixture was then quenched with ice water, washedwith NaHCO₃ and brine and extracted with 2×100 mL of ethyl acetate. Theorganic layer was dried over magnesium sulphate and concentrated. Thecrude product was purified by column chromatography, eluting with 70% to80% ethyl acetate in hexanes, to give the compound of Formula I ofExample 1. (2.11 g, 94.6%) as a pale-yellowish solid. ¹H NMR (300 MHz,CDCl₃): δ (ppm) 8.10 (s, 1H), 7.28-7.25 (m, 3H), 7.20 (dd, 2H), 6.82 (d,1H), 6.79 (d, 1H), 6.65 (d, 1H), 6.18 (wt, 1H), 6.14 (wt, 1H), 4.90-4.65(m, 2H), 4.60 (td, 1H), 4.35 (dd, 1H), 4.25 (dd, 1H), 4.05 (td, 1H),3.95 (dd, 1H), 3.30 (d, 1H), 3.28 (dd, 1H), 3.16 (d, 1H), 2.90 (dd, 1H),2.85 (dd, 1H), 2.75 (s, 3H), 1.41 (s, 3H).

In a similar manner to the above general procedure, the compounds ofFormula I of Examples 2-24 shown in Table 5 were synthesized.

Example 25

The compound of Formula I of Example 25,(2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-N-[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]-3-phenyl-propanamidewas prepared according to the following synthetic procedure:

(a) Preparation of tert-butyl 2-morpholinoacetate

To a stirred solution of tert-butyl bromoacetate (8.47 mL, 57.4 mmol) inTHF (50 mL) was added a 1:1 mixture of triethylamine (8 mL, 57.4 mmol)and morpholine (5.02 mL, 57.4 mmol), dropwise (a mild exotherm wasobserved) and the resulting white suspension was stirred at 60° C. for 2h. The mixture was diluted with water (100 mL) and saturated sodiumcarbonate (50 mL) and extracted with ethyl acetate (2×50 mL). Thecombined organics were washed with saturated sodium carbonate (100 mL),water (3×50 mL), and brine (50 mL). The organic phase was dried overanhydrous sodium sulfate, filtered and concentrated then chromatographedin 0%-100% ethyl acetate in hexanes. Product-containing fractions wereconcentrated in vacuo giving the title product (11.5 g, quantitative) asa pale yellow liquid. ¹H NMR (CDCl₃, 400 MHz): δ (ppm) 3.78-3.71 (m,4H), 3.10 (s, 2H), 2.59-2.54 (m, 4H), 1.46 (m, 9H).

(b) Preparation of 2-morpholinoacetic acid hydrochloride salt

Tert-butyl 2-morpholinoacetate (11 g, 54.7 mmol) was stirred with HCl,4M in dioxane (54 mL), giving a white precipitate (a mild exotherm wasobserved) which slowly dissolved with stirring at room temperature. Tenminutes after complete dissolution, the mixture solidified. Then themixture was warmed to 60° C. and the thick suspension was stirredvigorously overnight. The mixture was then cooled to room temperature,diluted with diethyl ether (60 mL) and filtered to collect the titlecompound (8 g, 80%) as a white solid. ¹H NMR (CD₃OD, 400 MHz): δ (ppm)4.13 (s, 2H), 3.94 (brm, 4H), 3.41 (brm, 4H).

(c) Preparation of benzyl(2S)-2-(tert-butoxycarbonylamino)-3-phenyl-propanoate

To a stirred solution of Boc-Phe-OH (10 g, 37.7 mmoL) in DMF (50 mL) wasadded potassium carbonate (7.81 g, 56.5 mmol) followed by benzylchloride (4.55 mL, 39.6 mmol) and the resulting suspension was stirredat 60° C. for 3 d. The mixture was diluted with water (400 mL) andextracted with ethyl acetate (75 mL, 2×25 mL). The combined organicswere washed with brine (200 mL), water (3×100 mL) and brine (50 mL). Theorganic phase was dried over anhydrous sodium sulfate, filtered andconcentrated then chromatographed on silica gel eluting with 0%-20%ethyl acetate in hexanes. The product-containing fractions wereconcentrated in vacuo giving the title compound (12.84 g, 95%) as awhite solid.

In a similar manner to the above general procedure, benzyl(2S)-2-(tert-butoxycarbonylamino)-4-methyl-pentanoate was synthesized.

(d) Preparation of benzyl (2S)-2-amino-3-phenyl-propanoate hydrochloride

Benzyl (2S)-2-(tert-butoxycarbonylamino)-3-phenyl-propanoate (12.8 g, 36mmol) was stirred in HCl, 2 M in diethyl ether (90 mL) and HCl, 4 M indioxane (18 mL) and the resulting mixture was stirred overnight at roomtemperature. The mixture was then diluted with hexanes (100 mL) andfiltered to collect the title compound (7.98 g, 76%) as a fine whitepowder. ¹H NMR (CD₃OD, 400 MHz): δ (ppm) 7.40-7.15 (m, 10H), 5.23 (s,2H), 4.36-4.31 (m, 1H), 3.26-3.12 (m, 2H).

(e) Preparation of benzyl(2S)-2-[[(2S)-2-(tert-butoxycarbonylamino)-3-(difluoromethoxy)propanoyl]amino]-3-phenyl-propanoate(I(g)(ii))

(2S)-2-(tert-butoxycarbonylamino)-3-(difluoromethoxy)propanoic acid (1.0g, 3.92 mmol), benzyl (2S)-2-lamino-3-phenyl-propanoate (1.2 g, 4.11mmol) and HOBt hydrate (0.66 g, 4.31 mmol) were stirred in DCM (20 mL).The resulting mixture was treated with EDC hydrochloride (0.83 g, 4.31mmol), cooled to 0° C. and treated with DIPEA (0.715 mL, 4.11 mmol). Themixture was warmed to room temperature and stirred overnight. Themixture was diluted with DCM (30 mL) and washed with saturated sodiumbicarbonate (2×50 mL). The organic phase was dried over anhydrous sodiumsulfate, filtered and concentrated in vacuo then chromatographed in0%-40% ethyl acetate in hexanes. The product-containing fractions wereconcentrated in vacuo giving the compound of Formula II(g)(ii) (1.9 g,98%) as a waxy solid. ¹H NMR (CDCl₃, 400 MHz): δ (ppm) 7.40-6.95 (m,10H), 6.71 (m, 1H), 6.14 (t, J=74 Hz, 1H), 5.19-5.09 (m, 2H), 4.95-4.85(m, 1H), 4.40-4.20 (m, 2H), 3.98-3.90 (m, 1H), 3.19-3.10 (m, 2H), 1.44(s, 9H).

(f) Preparation of benzyl(2S)-2-[[(2S)-2-amino-3-(difluoromethoxy)propanoyl]amino]-3-phenyl-propanoatehydrochloride (XVI(a))

Benzyl(2S)-2-[[(2S)-2-(tert-butoxycarbonylamino)-3(difluoromethoxy)propanoyl]amino]-3-phenyl-propanoate (1.9 g, 3.86 mmol)was stirred in HCl, 2M in diethyl ether (12 mL), at room temperatureovernight. The resulting suspension was diluted with hexanes and thefiltered to collect the compound of Formula XVI(a) (1.65 g, quantitativeyield) as a white solid. The product was used directly in the subsequentreaction.

(g) Preparation of benzyl(2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-3-phenyl-propanoate (XVII(a))

To a stirred solution of benzyl(2S)-2-[[(2S)-2-amino-3-(difluoromethoxy)propanoyl]amino]-3-phenyl-propanoatehydrochloride (1.65 g, 3.84 mmol), 2-morpholinoacetic acid hydrochloride(768 mg, 4.23 mmol) and HOBt hydrate (648 mg, 4.23 mmol) in DCM (20 mL)was added EDC hydrochloride (811 mg, 4.23 mmol). The resulting mixturewas cooled to 0° C. and treated with DIPEA (0.736 mL, 4.23 mmoL),dropwise, warmed to room temperature and stirred overnight. The mixturewas diluted with DCM (30 mL) and washed with saturated sodiumbicarbonate (2×50 mL). The organic phase was dried over anhydrous sodiumsulfate, filtered and concentrated in vacuo then chromatographed onsilica gel eluting with 0%-100% ethyl acetate in hexanes. Theproduct-containing fractions were concentrated in vacuo giving thecompound of Formula XVII(a) (1.54 g, 77%) as a white solid. ¹H NMR(CDCl₃, 400 MHz): δ (ppm) 7.72 (m, 1H), 7.35-6.90 (m, 10H), 6.12 (t,J=74 Hz, 1H), 5.14-5.04 (m, 2H), 4.81-4.75 (m, 1H), 4.65-4.55 (m, 1H),4.26-4.20 (m, 1H), 3.93-3.87 (m, 1H), 3.65-3.50 (m, 4H), 3.15-2.90 (m,4H), 2.45-2.35 (m, 4H).

In a similar manner to the above general procedure, the compounds shownin Table 6 were synthesized.

(h) Preparation of(2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-3-phenyl-propanoic acid (XVIII(a))

A stirred solution of benzyl(2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-3-phenyl-propanoate(1.54 g, 2.96 mmol) in THF (10 mL) was treated with palladium (10 wt. %on activated carbon) (157 mg, 0.148 mmol) and stirred under anatmosphere of hydrogen, balloon pressure, for 1 h. The mixture was thenfiltered through a pad of Celite™ and concentrated in vacuo giving thecompound of Formula XVIII(a) (1.27 g, quantitative yield) as colourlessfoam. ¹H NMR (CDCl₃, 400 MHz): δ (ppm) 8.09 (m, 1H), 7.24-7.05 (m, 5H),6.10 (t, J=74 Hz, 1H), 5.6 (brs, 1H), 4.70-4.60 (m, 2H), 4.15-4.01 (m,1H), 3.95-3.85 (m, 1H), 3.70-3.55 (m, 4H), 3.25-2.90 (m, 4H), 2.65-2.50(m, 4H).

In a similar manner to the above general procedure, the compounds shownin Table 7 were synthesized.

(i) Preparation of (2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2morpholinoacetyl)amino]propanoyl]amino]-N-[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]-3-phenyl-propanamide(Example-25)

To a stirred solution of(2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)-amino]propanoyl]amino]-3-phenyl-propanoic acid (200 mg, 0.46 mmol),(2S)-2-amino-4-methyl-1-(2-methyloxiran-2-yl)pentan-1-onetrifluoroacetate (133 mg, 0.46 mmol) and HOBt hydrate (71 mg, 0.46 mmol)in THF (10 mL) cooled to 0° C. was added HBTU (176 mg, 0.46 mmol)followed by DIPEA (162 μL, 0.93 mmol). The mixture was warmed to roomtemperature and stirred for 4 h. The mixture was diluted with DCM (40mL) and washed with saturated sodium bicarbonate (2×50 mL). The organicphase was dried over anhydrous sodium sulfate, filtered and concentratedthen chromatographed on silica gel eluting with 50%-100% ethyl acetatein hexanes. The product-containing fractions were concentrated in vacuoand triturated with a 1:1 mixture of hexanes:diethyl ether giving thecompound of Formula I of Example 25 (108 mg, 40%) as a pale solid. ¹HNMR (CDCl₃, 400 MHz): δ (ppm) 7.78 (m, 1H), 7.31-7.15 (m, 5H), 6.71 (m,1H), 6.22 (t, J=74 Hz, 1H), 6.10 (m, 1H), 4.65-4.49 (m, 3H), 4.30-4.20(m, 1H), 4.09-4.00 (m, 1H), 3.75-3.63 (m, 4H), 3.25-2.80 (m, 5H),2.55-2.45 (m, 4H), 2.17 (s, 3H), 1.55-1.18 (m, 3H), 0.95-0.85 (m, 6H).

In a similar manner to the above general procedure, the compounds ofFormula I of Examples 26-33 shown in Table 8 were synthesized.

C. Biological Assays Cells and Cell Culture

Human multiple myeloma cell lines 8226, H929, JJN3, KMH11, KMS11, KMS18,LP1, MM1S, OPM2 and U266 were grown in Iscove modified Dulbecco's medium(IMDM). Human leukemia cell lines K562, OCI-AML2 and U937 were culturedin RPMI-1640 medium. Primary peripheral blood mononuclear cells wereisolated from multiple myeloma patients by Ficoll density gradientcentrifugation and bone marrow aspirates were obtained from multiplemyeloma patients at the Princess Margaret Cancer Centre of theUniversity Health Network (UHN; Toronto, ON, Canada). Primary cells werecultured in IMDM. The collection and use of human tissue for this studywere approved by the UHN institutional ethics review board. All cellculture media were obtained from the Ontario Cancer Institute TissueCulture Media Facility (Toronto, ON, Canada) and were supplemented with10% fetal calf serum, 100 μg/mL penicillin, and 100 U/mL streptomycin(Hyclone, Logan, Utah). All cells were grown in a humidified incubatorat 37° C. with 5% CO₂.

Proteasome Enzymatic Activity (Tumor Cell Lysates)

Cells were harvested by centrifugation at 1,200 rpm at room temperature.Cell pellets were washed with PBS and lysed with assay lysis buffer (50mM HEPES (N-2-hydroxyethylpiperazine-N′-2-ethanesulfonic acid), pH 7.5;150 mM NaCl; 1% Triton X-100; 2 mM ATP). Cell lysates were incubated onice for 30 minutes, mixed by vortex every 5 minutes, and thencentrifuged at 12,000 g for 10 minutes. The supernatant was transferredto a 96-well plate. For each assay, 10 μg of total protein wereincubated for 1 hour at 37° C. with increasing concentrations (1 nM to10 μM) of test compound diluted in assay buffer (50 mM Tris-HCl(tris(hydroxymethyl)aminomethane-HCl), pH 7.5; 150 mM NaCl). DMSO alonewas used as a control in every assay plate. After incubation, a specificfluorogenic proteasome substrate was added to each assay reaction at afinal concentration of 40 μM in a total volume of 100 μL.N-Succinyl-Leu-Leu-Val-Tyr-7-amino-4-methylcoumarin(Suc-Leu-Leu-Val-Tyr-AMC) was used for measuring chymotrypsin-like(CT-L) activity, t-butoxycarbonyl-Leu-Arg-Arg-7-amino-4-methylcoumarin(Boc-Leu-Arg-Arg-AMC) for trypsin-like (T-L) activity, andbenzyloxycarbonyl-L-leucyl-L-leucyl-L-glutamyl-7-amino-4-methylcoumarin(Z-Leu-Leu-Glu-AMC) for caspase-like (C-L) activity. The excitationwavelength was set at 360 nm and the fluorescence emission wavelength ofAMC was detected at 460 nm. The fluorescence of free AMC released duringthe enzymatic reaction was measured with a SpectraMax M5 fluorescentspectrophotometric plate reader (Molecular Devices, Sunnyvale, Calif.).AMC release rate was measured at 37° C. in a kinetic mode, recordingevery 5 minutes for 30 minutes. Experiments were performed in triplicateand repeated at least twice.

Cell Viability Assays

Cellular viability was primarily assessed by3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium(MTS) assay according to the manufacturer's instructions (Promega;Madison, Wis.). Cells were first seeded at a density of 10,000 cells perwell in tissue culture-treated 96-well plates. Two hours after seeding,cells were treated with compounds for 72 hours at concentrations asindicated. As a control, cells were treated with DMSO alone in everyassay plate. Following treatment and the MTS assay, cell viability wasindependently confirmed by reading the optical density (O.D.) at 490 nmand by exclusion of trypan blue stain (Invitrogen; Burlington, ON,Canada). The viability of primary mononuclear cells was determined bystaining with Annexin V.

Table 9 summarizes data obtained for representative compounds of FormulaI for cell viability and CT-L proteasome activity using OCI-AML-2 andKMS-11 cell lines.

Proteases Purified from Thermoplasma acidophilum

Increasing concentrations (0, 0.26, 0.519, 1.0375, 2.075, 4.15 and 8.3μM) of compounds of Formula (I) and bortezomib were incubated with 1 μMpurified beta subunits of proteasomes isolated from Thermoplasmaacidophilum in assay buffer supplemented with 2 mM ATP. DMSO alone wasused as a control. After 1 hour of incubation at 37° C., theSuc-Leu-Leu-Val-Tyr-AMC substrate was added at a final concentration of40 μM and CT-L proteasome activity was measured as described above fortumor cell lysates.

FIG. 1 shows the effect of a representative of compounds of Formula I(the compound of Example 1) on the enzymatic activity of purifiedproteasomes, compared to bortezomib and shows that the compound ofFormula 1 of Example 1 disrupts the ubiquitin-proteasome system.Purified beta proteasome subunits from the archaebacteria Thermoplasmaacidophilum (A) and whole cell lysates from the human myeloma cell lineLP1 (B) were used in the study.

Immunoblotting Assay:

Whole cell lysates were prepared from LP1 cells in RIPA lysis buffer.Anti-ubiquitin antibody was purchased from Cell Signaling TechnologyInc, (Danvers, Mass.) and anti-tubulin antibody was purchased fromSigma-Aldrich (St. Louis, Mo.). Secondary horseradishperoxidase-conjugated goat anti-mouse or anti-rabbit IgG was purchasedfrom Amersham Bioscience (Piscataway, N.J.). Detection was performedusing an enhanced chemiluminescence kit from Pierce, (Rockford, Ill.).

LP1 cells exposed to compounds of Formula I demonstrated atime-dependent and dose-dependent increase in the abundance of highmolecular weight ubiquitylated proteins detected by immunoblot, usingtubulin as a loading control bortezomib; IB, immunoblot. Specifically,the compound of Examples 1 & 25 were tested and showed an IC₅₀<50 nM.

Combination Assays: Viability of Myeloma LP1 Cells in Culture

To examine whether compounds of Formula I can be combined with otherconventional and newer anti-multiple myeloma agents, such asdexamethasone and bortezomib, respectively, LP1 myeloma cells weretreated for 72 hours with increasing concentrations of compounds ofFormula I in combination with dexamethasone or bortezomib. Afterincubation, cell growth and viability was measured by the MTS assay. Thecombination index (CI) analysis, where a CI<1 indicates synergy betweentwo drugs, a CI=1 indicates additivity, and a CI>1 indicates antagonism,was used to determine whether the cytotoxicity produced by thecombinations with compounds of Formula I were synergistic, additive, orantagonistic.

The effects of combining these agents with a representative of compoundsof Formula I i.e. the compound of Example 1 on the viability of myelomaLP1 cells in culture were assessed. LP1 cells were treated for 72 hourswith increasing concentrations of the compound of Example 1 incombination with dexamethasone or bortezomib. After incubation, cellgrowth and viability was measured by the MTS assay.

The combination of the compound of Example 1 and bortezomib wassynergistic with Combination Index values of 0.41, 0.46, and 0.88 atFraction affected (Fa) levels of 0.39, 0.58, and 0.6, respectively (FIG.2A).

Thus using low doses of bortezomib may limit its off-target activity andassociated adverse effects while allowing for a more efficient,synergistic, and specific blockade of CT-L proteasome activity incombination with a compound of Formula 1 such as the compound of Example1.

The combination of the compound of Example 1 and dexamethasone wassynergistic with Combination Index values of 0.41, 0.44, and 0.5 atFraction affected levels of 0.43, 0.5, and 0.64, respectively (FIG. 2B).

The data provides the rationale for combining the compound of Example 1with another agent such as bortezomib to achieve useful proteasomeinhibition and antitumor activity, which may allow for use of lowerdoses of agents such as bortezomib and potentially reduced side effects.

Cell Death in Primary Myeloma Cells Preferential Over NormalHematopoietic Cells:

The viability of leukemia and myeloma cells treated with compounds ofFormula I or bortezomib was assessed with the use of a CellTiter 96™AQueous One Solution Cell Proliferation Assay (Promega, Madison, Wis.),which is a form of the3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazoliuminner salt (MTS) assay, or with fluorescence-based Alamar Blue cellviability reagent (Invitrogen, Carlsbad, Calif.) according tomanufacturer's instructions and as described previously [J. Natl. CancerInst. 2007, 99(10), 811-822; Hum. Reprod. 2007, 22(5), 1304-1309] or bytrypan blue staining.

Apoptosis was measured by staining cells treated with compounds ofFormula I with annexin V-fluorescein isothiocyanate and propidium iodide(both from Biovision Research Products, Mountain View, Calif.) and flowcytometry according to manufacturer's instructions and as previouslydescribed [Blood. 2005, 105(10), 4043-4050]. Experiments were performedat least in duplicate and repeated at least twice (n=4-20 data points).Viable primary myeloma cells were identified by staining withphycoerythrin-conjugated mouse monoclonal anti-CD138 antibody (20 μL/106cells; Beckman Coulter, Brea, Calif.). The percentage of myeloma cellsthat were CD138 positive and annexin V negative after compounds ofFormula (I) treatment compared with untreated samples was quantified asa marker of cell viability as previously described [Blood. 2007,109(12), 5430-5438].

Effects of a representative of compounds of Formula I (the compound ofExample 1) on the viability of primary malignant and normalhematopoietic cells isolated from patient samples was also studied. Themononuclear cells from a bone and marrow of a patient with myeloma wereincubated for 24 hours with increasing concentrations of the compound ofExample 1 (Patient 1); the peripheral blood mononuclear cells from apatient with plasma cell leukemia were incubated for 24 hours withincreasing concentrations of the compound of Example 1 (Patient 2); anda primary myeloma patient's samples were treated with increasingconcentrations of the compound of Example 1 (Patient 3). Viability ofnormal hematopoietic cells (CD138−) and myeloma cells (CD138+) weremeasured by flow cytometry with PE-labeled anti-CD138 and FITC-labeledAnnexin V co-staining.

Data represent the percentage of viable cells from each patient sample(FIG. 3). FIG. 3 shows the effects of the compound of Example 1 on thecell viability of primary samples from myeloma patients detected byAnnexin V staining and flow cytometry following 24 hours of treatment,relative to vehicle control. The compound of Example 1 selectivelyreduced the viability of primary CD138+ myeloma cells over CD138− normalhematopoietic cells isolated from the bone marrow of patients withmultiple myeloma (FIGS. 3A and 3C) or from the peripheral blood of apatient with plasma cell leukemia (FIG. 3B). The compound of Example 1induced cell death in the plasma cells of the myeloma patients atnanomolar concentrations. The compound of Example 1 was less cytotoxicto the normal mononuclear hematopoietic cells with an LD₅₀>2.5 μM. Bycontrast, carfilzomib demonstrates a much narrower therapeutic indexbetween CD138+ and CD-138− in patient samples [Trudel et al. ASH 2009,Poster Board 1-867].

Murine Red Blood Cells and Organ Homogenates

All mouse experiments were performed in accordance with approval fromthe Ontario Cancer Institute institutional animal review board. Five- tosix-week-old male non-obese diabetic/severe combined immunodeficient(NOD/SCID) mice were grouped randomly (n=3 mice per group). Mice wereadministered vehicle (5% DMSO, 20% Cremophor) or compounds of Formula Iat different doses either intravenously or by oral gavage, and venousblood samples (20-50 μL) were collected from each mouse over 24 hours.Blood samples were mixed with heparin (APP Pharmaceuticals; Schaumburg,Ill.) in 0.5 mL tubes in accordance with the manufacturer'sinstructions. After centrifugal separation at 3,000 g for 10 minutes,red blood cells (RBCs) in the bottom layer were transferred into a newtube and stored at −70° C. until use. RBCs were lysed with assay lysisbuffer and incubated on ice for 30 minutes, mixing by vortex every 5minutes, and then centrifuged at 12,000 g for 10 minutes. Thesupernatant was transferred to a 96-well plate and proteasome activitywas measured as described in above for tumor cell lysates.

To evaluate proteasome activity of compounds of Formula I in the organsof treated mice, five- to six-week-old male NOD/SCID mice weresacrificed by CO₂ inhalation 4 hours after oral gavage with controlvehicle and administered representative of compounds of Formula I atdoses of 30 mg to 100 mg. The brain, liver, heart, lung, kidney, femursand bone marrow were removed, washed with PBS, and stored at −70° C.until use. Prior to analysis, mouse organs were thawed and homogenizedon ice in assay lysis buffer. Femurs were cut at both ends and bonemarrow was flushed out with assay lysis buffer. Organ homogenates werecentrifuged at 13,000 g for 30 minutes at 4° C. and the supernatant wasused for measuring proteasome activity as described above for tumor celllysates.

Proteasome subunit activity (Chymotrypsin-like, Trypsin-like,Caspase-like, CT-L, T-L, C-L, respectively) were monitored over thecourse of 24 hrs following oral administration of representativecompounds of Formula I. NOD/SCID mice were treated with the compoundfrom Example 1 (50 mg/kg by oral gavage) and the compound from Example26 (60 mg/kg by oral gavage) or vehicle control for up to 24 hours, asdescribed above.

Table 10 summarizes the data for the representative compounds of Formula(I); the compounds of Examples 1 and 26. As can be seen from the data inTable 10, the compounds of Examples 1 and 26 display pharmacodynamicactivity following oral administration to mice.

National Cancer Institute (NCI) Screening Panel:

Representative compounds of Formula I were screened using the NationalCancer Institute (NCI) screening panel, which consists of a panel of 60different human tumor cell lines, representing leukemia [CCRF-CEM, HL-60(TB), K-562, MOLT-4, SR], melanoma [LOX IMVI, MALME-3M, M14,SMDA-MB-435, SK-MEL-2, SK-MEL-28, SK-MEL-5, UACC-257 and UACC-62] andcancers of the lung [A549/ATCC, EKVX, HOP-62, HOP-93, NCI-H226, NCI-H23,NCI-H322M, NCI-H460], colon [COLO 205, HCT-116, HCT-15, HT29, KM12,SW-620], brain [SF-268, SF-295, SF-539, SNB-19, SNB-75, U251], ovary[IGROV1, OVCAR-3, OVCAR-4, OVCAR-5, OVCAR-8, NCI/ADR-RES, SK-OV-3],breast [MCF7, MDA-MB-231, BT-549, T-47D, MDA-MB-468], prostate [PC-3,DU-145], and renal [786-0, A498, ACHN, CAKI-1, RXF-393, SN12C, TK-10,UO-31] cancers.

After 24 h, two plates of each cell line are fixed in situ with TCA, torepresent a measurement of the cell population for each cell line at thetime of drug addition (T_(z)). Experimental drugs are solubilised indimethyl sulfoxide at 400-fold the desired final maximum testconcentration and stored frozen prior to use. At the time of drugaddition, an aliquot of frozen concentrate is thawed and diluted totwice the desired final maximum test concentration with complete mediumcontaining 50 μg/ml gentamicin. Additional four, 10-fold or 1 log serialdilutions are made to provide a total of five drug concentrations pluscontrol. Aliquots of 100 μl of these different drug dilutions are addedto the appropriate microtiter wells already containing 100 μl of medium,resulting in the required final drug concentrations.

Following drug addition, the plates are incubated for an additional 48 hat 37° C., 5% CO₂, 95% air, and 100% relative humidity. For adherentcells, the assay is terminated by the addition of cold TCA(trichloroacetic acid). Cells are fixed in situ by the gentle additionof 50 μl of cold 50% (w/v) TCA (final concentration, 10% TCA) andincubated for 60 minutes at 4° C. The supernatant is discarded, and theplates are washed five times with tap water and air dried.Sulforhodamine B (SRB) solution (100 μl) at 0.4% (w/v) in 1% acetic acidis added to each well, and plates are incubated for 10 minutes at roomtemperature. After staining, unbound dye is removed by washing fivetimes with 1% acetic acid and the plates are air dried. Bound stain issubsequently solubilised with 10 mM trizma base, and the absorbance isread on an automated plate reader at a wavelength of 515 nm. Forsuspension cells, the methodology is the same except that the assay isterminated by fixing settled cells at the bottom of the wells by gentlyadding 50 μl of 80% TCA (final concentration, 16% TCA). Using the sevenabsorbance measurements [time zero, (T_(i)), control growth, (C), andtest growth in the presence of drug at the five concentration levels(T_(i))], the percentage growth is calculated at each of the drugconcentration levels. Percentage growth inhibition is calculated as:[(T_(i)−T_(z))/(C−T_(z))]×100 for concentrations in which T_(i)>/=T_(z)and [(T_(i)−T_(z))/T_(z)]×100 for concentrations in which T_(i)<T_(z).

Three dose response parameters are calculated for each experimentalagent. Growth inhibition of 50% (GI₅₀) is calculated from[(T_(i)−T_(z))/(C−T_(z))]×100=50, which is the drug concentrationresulting in a 50% reduction in the net protein increase (as measured bySRB staining) in control cells during the drug incubation. The drugconcentration resulting in total growth inhibition (TGI) is calculatedfrom T_(i)=T_(z). The LC₅₀ (concentration of drug resulting in a 50%reduction in the measured protein at the end of the drug treatment ascompared to that at the beginning) indicating a net loss of cellsfollowing treatment is calculated from [(T_(i)−T_(z))/T_(z)]×100=−50.Values are calculated for each of these three parameters if the level ofactivity is reached. However, if the effect is not reached or isexceeded, the value for that parameter is expressed as greater or lessthan the maximum or minimum concentration tested.

The results obtained from this study shows compounds of Formula I areeffective against the cell lines of the 60 human tumor cell lines panel.Inhibition of human cancer cell lines in vitro by representativecompounds of Formula (I) are shown in Table 11 (Example 1), Table 12(Example 25), Table 13 (Example 26) and Table 14 (Example 29).

Inhibition of Tumor Growth in Mouse Xenograft Models: Efficacy on TumorGrowth in Hollow Fiber Assay (HFA)

Hollow fibre assay in vivo pharmacodynamic studies were carried out.This in vivo animal model uses semi-permeable biocompatible fibres thatare filled with cancer cells, heat-sealed and implanted surgically (s.c.or i.p.) in mice or rats, which can then be treated withchemotherapeutics. Many different cell lines from different tissueorigins and cellular characteristics can be encapsulated within thefibres, providing a cost-effective screening method.

The Oncology Program Screening and Characterization Strategy group atNCI uses HFA, which provides quantitative indices of drug efficacy withminimal expenditures of time and materials. Thus, the HFA is beingutilized as the initial in vivo experience for compounds of Formula I.

A total of 3 different tumor lines are prepared for each experiment sothat each mouse receives 3 intraperitoneal implants (1 of each tumorline) and 3 subcutaneous implants (1 of each tumor line). A compound isconsidered for xenograft testing if it produces cell kill of any cellline at either dose level evaluated, or it has a combined ip+sc score of20 or greater, a sc score of 8 or greater. This scoring system has beenvalidated by DCTDC statisticians in CTEP to represent a level ofdetection expected to score current “standard” agents as active.

The compound of Example 1 was evaluated in an HFA assay via ipadministration at two doses; a 75 mg/kg/dose and a 35.5 mg/kg/dose,QD×4. A standard panel of 12 tumor cell lines was used for hollow fiberscreening of compound of Formula I. These include NCI-H23 and NCI-H522for non-small cell lung cancer, MDA-MB-231 for breast cancer,MDA-MB-435, LOX IMVI and UACC-62 for melanoma, SW-620 and COLO 205 forcolon cancer, OVCAR-3 and OVCAR-5 for ovarian cancer, and U251 andSF-295 for CNS (central nervous system) cancer. The compound of Example1 of Formula I produced cell killing of multiple cell lines at either ofthe two doses (75 mg/kg/dose and 35.5 mg/kg/dose).

Efficacy on Tumor Growth in Leukemia AML2 Xenograft Models:

Sublethally irradiated NOD-SCID mice bearing an established human tumorxenograft derived from RL and BALB/c mice challenged with the murinetumor cell line AML2 were treated twice weekly on days 1 and 2 (QD×2)with a dose of 30 mg/kg to 200 mg/kg of the compound of Example 1 byoral gavage. Dosing began on Day 6 post tumor challenge. Resultsdemonstrated that compounds of Formula I exhibit antitumor response. Forexample, the compound of Example 1 of Formula I exhibits an antitumorresponse of greater than 40% tumor growth inhibition in the AML2 mousexenograft leukemia model at 30 mg/kg with no observed gross adverseeffects including reductions in body weight or alterations in behaviour.

Efficacy on Tumor Growth Inhibition in Myeloma MM.1S Mouse XenograftModels:

The mice were irradiated (200 rads) using a Co60 irradiator source.After 24 hrs, each mouse was inoculated subcutaneously with 5×10⁶ MM.1Stumor cells in 0.1 ml PBS for tumor development. Treatments were startedwhen the tumor volume reached 100 mm³. Each treatment group consisted of10 mice. The compound of Example 1 was administrated to thetumor-bearing mice according to a specific predetermined regimen. Thecompound from Example 1 at dose levels of 50 mg/kg (p.o, qd×28 days) and100 mg/kg (p.o, days 1, 3, 5/wk×4 wks) produced statically significantantitumor activity vs. control with no observed gross adverse effectsincluding reductions in body weight or alterations in behaviour.

While the present application has been described with reference to whatare presently considered to be the preferred examples, it is to beunderstood that the present application is not limited to the disclosedexamples. To the contrary, the present application is intended to covervarious modifications and equivalent arrangements included within thespirit and scope of the appended claims.

All publications, patents and patent applications are hereinincorporated by reference in their entirety to the same extent as ifeach individual publication, patent or patent application wasspecifically and individually indicated to be incorporated by referencein its entirety. Where a term in the present application is found to bedefined differently in a document incorporated herein by reference, thedefinition provided herein is to serve as the definition for the term.

TABLE 1 Compound Yield # Structure Nomenclature Appearance (%) II(b)(ii)

Benzyl-(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3-(difluoromethoxy)propanoyl]- amino]-3-methoxy- propanoate off-whitepowder 71 ¹H NMR (300 MHz CDCl₃): δ (ppm): 7.41-7.39 (m, 5H), 7.18 (td,1H), 6.21 (wt, 1H), 5.25-5.20 (m, 1H), 5.19 (s, 2H), 4.82 (td, 1H), 4.42(br s, 1H), 4.31 (td, 1H), 4.20-4.15 (m, 2H), 4.01 (dd, 1H), 3.25 (s,3H), 1.41 (s, 9H). II(c)(ii)

Benzyl-(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3-methoxy-propanoyl]amino)- 3- (difluoromethoxy)propanoate off-whitepowder 86 ¹H NMR (300 MHz CDCl₃): δ (ppm): 7.42-7.38 (m, 5H), 7.20 (td,1H), 6.23 (wt, 1H), 5.22-5.26 (m, 1H), 5.18 (s, 2H), 4.79 (td, 1H), 4.41(br s, 1H), 4.33 (td, 1H), 4.19-4.16 (m, 2H), 4.03 (dd, 1H), 3.26 (s,3H), 1.43 (s, 9H). II(d)(ii)

Benzyl-(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3-(difluoromethoxy)propanoyl] amino]-4-methyl-pentanoate white solid 76 ¹HNMR (CDCl₃, 400 MHz): δ 7.42-7.35 (m, 5H), 6.87-6.81 (m, 1H), 6.13 (t, J= 74 Hz, 1H), 5.22-5.17 (m, 2H), 4.89-4.77 (m, 2H), 4.33- 4.25 (m, 1H),4.18-4.09 (m, 2H), 1.75-1.61 (m, 2H), 1.54-1.39 (m, 1H), 0.99-0.87 (m,6H). II(e)(ii)

Benzyl-(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-4-methyl-pentanoyl]amino]-3- (difluoromethoxy)propanoate clear sticky oil85 ¹H NMR (CDCl₃, 400 MHz): δ 7.40-7.31 (m, 5H), 6.89-6.83 (m, 1H), 6.14(t, J = 74 Hz, 1H), 5.24-5.18 (m, 2H), 4.87-4.79 (m, 2H), 4.32- 4.26 (m,1H), 4.18-4.09 (m, 2H), 1.73-1.62 (m, 2H), 1.53-1.40 (m, 1H), 0.98-0.88(m, 6H). II(f)(ii)

benzyl (2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3-phenyl-propanoyl]amino]-3- (difluoromethoxy)propanoate white solid 94II(g)(ii)

Benzyl-(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3-(difluoromethoxy)propanoyl] amino]-3-phenylpropanoate white solid 78

TABLE 2 Compound Yield # Structure Nomenclature Appearance (%) II(b)(i)

(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3-(difluoromethoxy)propanoyl]- amino]-3-methoxypropanoic acid off-whitefoam  98 NMR (d₆-DMSO, 400 MHz): δ 8.36 (d, J = 8 Hz, 1H), 7.12 (d, J =8 Hz, 1H), 6.63 (t, J = 76 Hz, 1H), 4.57-4.51 (m, 1H), 4.37-4.29 (m,1H), 4.15-4.09 (m, 1H), 4.04-3.97 (m, 2H), 3.92-3.83 (m, 1H), 3.21 (s,3H), 1.37 (s, 9H). II(c)(i)

(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3- methoxy-propanoyl]amino]-3(difluoromethoxy)propanoic acid clear sticky oil  99 NMR (d₆-DMSO, 400MHz): δ 8.33 (d, 1H), 7.14 (d, J = 8 Hz, 1H), 6.63 (t, J = 75 Hz, 1H),4.59-4.49 (m, 1H), 4.38-4.27 (m, 1H), 4.17- 4.10 (m, 1H), 4.06-3.97 (m,2H), 3.95-3.80 (m, 1H), 3.22 (s, 3H), 1.38 (s, 9H). II(f)(i)

(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3-phenyl-propanoyl]amino]-3- (difluoromethoxy)propanoic acid white solid100 II(g)(i)

(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3-(difluoromethoxy)propanoyl] amino]-3-phenyl-propanoic acid white powder 98 II(d)(i)

(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-3-(difluoromethoxy)propanoyl] amino]-4-methyl-pentanoic acid off-whiteyellowish foam  66 ¹H NMR (d₆-DMSO, 400 MHz): 8.35 (d, 1H), 6.11 (t, J =74 Hz, 1H), 5.17-5.05 (m, 1H), 4.79-4.71 (m, 1H), 4.29-4.16 (m, 1H),4.11-4.01 (m, 1H), 1.68-1.52 (m, 2H), 1.50-1.27 (m, 1H), 1.38 (s, 9H),0.91- 0.83 (m, 6H). II(e)(i)

(2S)-2-[[(2S)-2-(tert- butoxycarbonylamino)-4-methyl-pentanoyl]amino]-3- (difluoromethoxy)propanoic acid clear oil  85¹H NMR (d₆-DMSO, 400 MHz): 8.37 (d, 1H), 6.13 (t, J = 74 Hz, 1H),5.15-5.01 (m, 1H), 4.81-4.75 (m, 1H), 4.28-4.15 (m, 1H), 4.13-4.02 (m,1H), 1.71-1.55 (m, 2H), 1.52-1.26 (m, 1H), 1.38 (s, 9H), 0.94- 0.82 (m,6H).

TABLE 3 Compound Formula and Yield # Structure Nomenclature Appearance(%) XIV(b)

C₂₅H₃₅F₂N₃O₈ ((S)-1-{(S)-1-[(S)-1- Benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo- ethylcarbamoyl]-2- methoxyethylcarbamoyl}-2-difluoromethoxyethyl)- carbamic acid tert-butyl ester off-white solid 85¹H-NMR (300 MHz, CDCl₃): δ 7.21-7.35 (m, 3H), 7.18 (dd, 2H), 6.80 (wd,1H), 6.72 (wd, 1H), 6.21 (w t, 1H), 5.29 (br s, 1H), 4.79 (td, 1H), 4.58(td, 1H), 4.36 (m, 1H), 4.35-4.12 (m, 2H), 4.10 (dd, 1H), 3.87 (dd, 1H),3.26 (d, 1H), 3.25 (s, 3H), 3.14 (dd, 1H), 2.87 (d, 1H), 2.87 (dd, 1H),1.49 (s, 3H), 1.43 (s, 9H). XIV(c)

C₂₅H₃₅F₂N₃O₈ ((S)-1-{(S)-1-[(S)-1- Benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo- ethylcarbamoyl]-2- difluoromethoxyethyl- carbamoyl}-2-methoxyethyl)-carbamic acid tert-butyl ester off-white powder 83 ¹H-NMR(300 MHz, CDCl₃): δ 7.20-7.28 (m, 3H), 7.20 (dd, 2H), 6.83 (wd, 1H),6.75 (wd, 1H), 6.71 (w t, 1H), 5.27 (br s, 1H), 4.81 (td, 1H), 4.60 (td,1H), 4.38 (m, 1H), 4.38-4.09 (m, 2H), 4.12 (dd, 1H), 3.91 (dd, 1H), 3.29(d, 1H), 3.26 (s, 3H), 3.16 (dd, 1H), 2.84 (d, 1H), 2.81 (dd, 1H), 1.50(s, 3H), 1 41 (s, 9H). XIV(d)

C₂₂H₃₅F₄N₃O₈ (S)-2-Difluoromethoxy- 1-{(S)-2-di- fluoromethoxy-1-[(S)-3-methyl-1-((R)-2-methyl- oxiranecarbonyl)- butylcarbamoyl]-ethylcarbamoyl}-ethyl)- carbamic acid tert-butyl ester off-white powder99 ¹H-NMR (CDCl₃, 300 MHz): δ 7.02 (d, J = 6 Hz, 1H), 6.74-6.64 (m, 1H),6.25 (t, J = 75 Hz, 1H), 6.21 (t, J = 75 Hz, 1H), 5.34-5.24 (m, 1H),4.69-4.58 (m, 3H), 4.44-4.24 (m, 4H), 4.10-4.04 (m, 1H), 3.99- 3.92 (m,1H), 3.24 (d, J = 6 Hz, 1H), 2.91-2.87 (m, 2H), 1.82-1.72 (m, 1H), 1.51(s, 3H), 1.46 (s, 9H), 0.96-0.90 (m, 6H). XIV(e)

C₂₄H₄₁F₂N₃O₇ ((S)-2-Difluoromethoxy- 1-{(S)-3- methyl-1-[(S)-3-methyl-1-((R)-2-methyl- oxiranecarbonyl)- butylcarbamoyl]-butylcarbamoyl}-ethyl)- carbamic acid tert-butyl ester white powder 70NMR (CDCl₃, 300 MHz): δ 6.98 (d, 1H), 6.74-6.64 (m, 1H), 6.22 (t, J = 75Hz, 1H), 5.33-5.24 (m, 1H), 4.69-4.58 (m, 3H), 4.44-4.24 (m, 4H),4.10-4.04 (m, 1H), 3.99-3.92 (m, 1H), 3.21 (d, J = 6 Hz, 1H), 2.94-2.85(m, 2H), 1.80-1.69 (m, 1H), 1.50 (s, 3H), 1.43 (s, 9H), 1.01-0.89 (m,12H). XIV(f)

C₂₇H₃₉F₂N₃O₇ ((S)-1-{(S)-1-[(S)-1- Benzyl-2-((R)- 2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-3- methyl- butylcarbamoyl}-2- difluoromethoxyethyl)-carbamic acid tert-butyl ester off-white powder 82 ¹H NMR (300 MHz,CDCl₃): δ (ppm): 7.32-7.20 (m, 3H), 7.13 (dd, 2H), 6.82 (wd, 1H), 6.70(wd, 1H), 6.51 (w t, 1H), 6.25 (t, J = 75 Hz, 1H), 5.26 (br s, 1H), 4.86(td, 1H), 4.58 (td, 1H), 4.36 (m, 1H), 4.32- 4.08 (m, 2H), 4.01 (dd,1H), 3.90 (dd, 1H), 3.24 (d, 1H), 3.12 (dd, 1H), 2.90 (d, 1H), 2.85 (dd,1H), 1.81-1.70 (m, 1H), 1.50 (s, 3H), 1.43 (s, 9H), 1.03-0.88 (m, 6H).XIV(g)

C₂₇H₃₉F₂N₃O₇ ((S)-1-{(S)-1-[(S)-1- Benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo- ethylcarbamoyl]-2- difluoromethoxy- ethylcarbamoyl}-3-methylbutyl)-carbamic acid tert-butyl ester off-white powder 87 ¹H NMR(300 MHz, CDCl₃): δ (ppm): 7.34-7.21 (m, 3H), 7.12 (dd, 2H), 6.79 (wd,1H), 6.73 (wd, 1H), 6.49 (wt, 1H), 6.24 (t, J = 75 Hz, 1H), 5.24 (br s,1H), 4.83 (td, 1H), 4.55 (td, 1H), 4.38 (m, 1H), 4.35- 4.03 (m, 2H),4.06 (dd, 1H), 3.88 (dd, 1H), 3.25 (d, 1H), 3.11 (dd, 1H), 2.89 (d, 1H),2.83 (dd, 1H), 1.84-1.75 (m, 1H), 1.52 (s, 3H), 1.42 (s, 9H), 1.02-0.91(m, 6H). XIV(h)

C₂₄H₄₁F₂N₃O₇ ((S)-1-{(S)-2- Difluoromethoxy-1-[(S)-3-methyl-1-((R)-2-methyl- oxiranecarbonyl)- butylcarbamoyl]-ethylcarbamoyl}-3- methylbutyl)-carbamic acid tert-butyl ester off-whitepowder 67 ¹H NMR (300 MHz, CDCl₃): δ (ppm): 6.81 (wd, 1H) 6.72 (wd, 1H),6.51 (wt, 1H), 6.25 (t, J = 75 Hz, 1H), 5.24 (br s, 1H), 4.83 (td, 1H),4.55 (td, 1H), 4.38 (m, 1H), 4.35-4.03 (m, 2H), 4.06 (dd, 1H), 3.88 (dd,1H), 3.25 (d, 1H), 3.11 (dd, 1H), 2.89 (d, 1H), 2.83 (dd, 1H), 1.80-1.71(m, 2H), 1.52 (s, 3H), 1.42 (s, 9H), 1.05-0.93 (m, 12H).

TABLE 4 Compound Formula and Yield # Structure Nomenclature Appearance(%) XV(b)

C₂₀H₂₇F₂N₃O₆ (free base) (S)-2-Amino-N-{(S)-1- [(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)- 2-oxo-ethylcarbamoyl]-2- methoxyethyl}-3-difluoromethoxypropionamide off-yellow solid 98 ¹H NMR (300 MHz,d₆-DMSO): δ (ppm): 7.39-7.25 (m, 3H), 7.24 (dd, 2H), 6.87 (wd, 1H), 6.66(wd, 1H), 6.55 (br s, 1H), 6.13 (w t, 1H), 6.02 (wt, 1H), 5.15 (br s,1H), 4.81 (td, 1H), 4.49 (td, 1H), 4.32 (m, 1H), 4.93-3.31 (m, 2H), 3.99(dd, 1H), 3.88 (dd, 1H), 3.55 (s, 3H). 3.21 (d, 1H), 3.12 (dd, 1H), 2.81(d, 1H), 2.78 (dd, 1H), 1.43 (s 3H). XV(c)

C₂₀H₂₇F₂N₃O₆ (free base) (S)-2-Amino-N-{(S)-1- [(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)- 2-oxo-ethylcarbamoyl]-2-difluoromethoxyethyl}-3- methoxypropionamide off-yellow solid 85 ¹H NMR(300 MHz, d₆-DMSO): δ (ppm): 7.33-7.27 (m, 3H), 7.25 (dd, 2H), 6.87 (d,1H), 6.59 (wd, 1H), 6.57 (br s, 1H), 6.09 (w t, 1H), 6.11 (t, 1H), 5.21(br s, 1H), 4.76 (td, 1H), 4.52 (td, 1H), 4.41 (m, 1H), 4.33-3.98 (m,2H), 3.95 (dd, 1H), 3.89 (dd, 1H), 3.51 (s, 3H). 3.18 (d, 1H), 3.09 (dd,1H), 2.83 (d, 1H), 2.76 (dd, 1H), 1.44 (s, 3H). XV(d)

C₁₇H₂7F₄N₃O₆ (free base) (S)-2-Amino-3- difluoromethoxy-N-{(S)-2-difluoromethoxy-1-[(S)-3- methyl-1-((R)-2- methyloxiranecarbonyl)-butylcarbamoyl]-ethyl}- propionamide sticky yellow powder 73 ¹H NMR (300MHz, d₆-DMSO): δ (ppm): 6.97 (d, 1H), 6.69-6.65 (m, 1H),6.45 (br.s, 2H),6.16 (t, J = 75 Hz, 1H), 6.13 (t, J = 75 Hz, 1H), 5.35-5.26 (m, 1H),4.69-4.58 (m, 3H), 4.44-4.24 (m, 4H), 4.10-4.04 (m, 1H), 3.99-3.92 (m,1H), 3.24 (d, J = 6 Hz, 1H), 2.91-2.87 (m, 2H), 1.72-1.69 (m, 1H), 1.49(s, 3H), 0.94-0.91 (m, 6H). XV(e)

C₁₉H₃₃F₂N₃O₅ (free base) (S)-2-((S)-2-Amino-3- difluoromethoxy-propionylamino)-4-methyl- pentanoic acid [(S)-3- methyl-1-((R)-2-methyloxiranecarbonyl)- butyl]-amide white powder 65 ¹H NMR (300 MHz,d₆-DMSO): δ (ppm): 6.89 (d, 1H), 6.70-6.59 (m, 1H), 6.55 (br. s, 2H),6.17, (t, J = 75 Hz, 1H), 5.35-5.24 (m, 1H), 4.71-4.63 (m, 3H),4.51-4.53 (m, 4H), 4.13-4.01 (m, 1H), 3.97-3.91 (m, 1H), 3.23 (d, 1H),2.98-2.81 (m, 2H), 1.78-1.65 (m, 1H), 1.48 (s, 3H), 0.98-0.83 (m, 12H).XV(f)

C₂₂H₃₁F₂N₃O₅ (free base) (S)-2-((S)-2-Amino-3- difluoromethoxy-propionylamino)-4-methyl- pentanoic acid [(S)-1- benzyl-2-((R)-2-methyloxiranyl)-2-oxo- ethyl]-amide off-white powder 62 ¹H NMR (300 MHz,d₆-DMSO): δ (ppm): 7.29-7.18 (m, 3H), 7.09 (dd, 2H), 6.74 (wd, 1H), 6.67(br. s, 2H), 6.65 (d, 1H), 6.48 (t, 1H), 6.19 (t, J = 75 Hz, 1H), 5.21(br s, 1H), 4.77 (td, 1H), 4.51 (td, 1H), 4.38- 4.34 (m, 1H), 4.19-4.05(m, 2H), 3.99 (dd, 1H), 3.95-3.92 (m, 1H), 3.18 (d, 1H), 3.14-3.16 (m,1H), 2.85 (d, 1H), 2.75-7.62 (m, 1H), 1.77-1.69 (m, 1H), 1.48 (s, 3H),0.97-0.86 (m, 6H). XV(g)

C₂₂H₃₁F₂N₃O₅ (free base) (S)-2-Amino-4-methyl- pentanoic acid {(S)-1-[(S)-1-benzyl-2-((R)-2- methyloxiranyl)-2-oxo- ethylcarbamoyl]-2-difluoromethoxyethyl}- amide off-white powder 76 ¹H NMR (300 MHz,d₆-DMSO): δ (ppm): 7.31-7.19 (m, 3H), 7.11 (dd, 2H), 6.76-6.68 (m, 1H),6.52 (br. s, 2H), 6.49 (d, 1H), 6.45 (t, 1H), 6.21 (t, J = 75 Hz, 1H),5.18 (br. s, 1H), 4.76-4.68 (m, 1H), 4.54-4.49 (m, 1H), 4.29-4.25 (m,1H), 4.15-4.01 (m, 2H), 3.98-3.91 (m, 1H), 3.87-3.82 (m, 1H), 3.15 (d,1H), 3.15-3.11 (m, 1H), 2.76 (d, 1H), 2.77-7.60 (m, 1H), 1.89-1.78 (m,1H), 1.47 (s, 3H), 0.98-0.87 (m, 6H). XV(h)

C₁₉H₃₃F₂N₃O₅ (S)-2-Amino-4-methyl- pentanoic acid {(S)-2-difluoromethoxy-1-[(S)-3- methyl-1-((R)-2- methyloxiranecarbonyl)-butylcarbamoyl]-ethyl}- amide off-white powder 89 ¹H NMR (300 MHz,d₆-DMSO): δ (ppm): 6.92 (wd, 1H), 6.72 (wd, 1H), 6.55-6.50 (m, 1H), 6.15(t, J = 75 Hz, 1H), 5.09 (br. s, 1H), 4.81-4.78 (m, 1H), 4.57-4.52 (m,1H), 4.28-4.19 (m, 1H), 4.17-4.02 (m, 2H), 3.99-3.87 (m, 1H), 3.73 (dd,1H), 3.17 (d, 1H), 3.07 (dd, 1H), 2.75 (d, 1H), 2.81-2.77 (m, 1H),1.73-1.69 (m, 2H), 1.49 (s, 3H), 0.98-0.91 (m, 12H).

TABLE 5 Example Yield # Structure Nomenclature Appearance (%)  2

2-Methyl-thiazole-5- carboxylic acid-((S)-1- {(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)- 2-oxo-ethylcarbamoyl]- 2-methoxy-ethylcarbamoyl}-2- difluoromethoxyethyl)- amide white yellowish powder73 ¹H NMR (300 MHz, CDCl₃): δ (ppm): 8.06 (s, 1H), 7.27-7.24 (m, 3H),7.18 (dd, 2H), 6.79 (d, 1H), 6.77 (d, 1H), 6.64 (d, 1H), 6.13 (wt, 1H),4.87-4.67 (m, 2H), 4.58 (td, 1H), 4.32 (dd, 1H), 4.27 (dd, 1H), 4.02(td, 1H), 3.91 (dd, 1H), 3.30 (s, 3H), 3.27 (d, 1H), 3.28 (dd, 1H), 3.16(d, 1H), 2.88 (dd, 1H), 2.83 (dd, 1H), 2.74 (s, 3H), 1.46 (s, 3H).  3

2-Methyl-thiazole-5- carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2- methyl-oxiranyl)-2-oxo- ethylcarbamoyl]-2-difluoromethoxyethyl- carbamoyl}- 2-methoxyethyl)- amide off-whitepowder 65 ¹H NMR (300 MHz, CDCl₃): δ (ppm): 8.07 (s, 1H), 7.28-7.26 (m,3H), 7.15 (dd, 2H), 6.81 (d, 1H), 6.82 (d, 1H), 6.71 (d, 1H), 6.21 (wt,1H), 4.91-4.82 (m, 2H), 4.62 (td, 1H), 4.38 (dd, 1H), 4.31 (dd, 1H),4.05 (td, 1H), 3.99 (dd, 1H), 3.29 (s, 3H), 3.27 (d, 1H), 3.25 (dd, 1H),3.15 (d, 1H), 2.91 (dd, 1H), 2.79 (dd, 1H), 2.71 (s, 3H), 1.49 (s, 3H). 4

2-Methyl-oxazole-5- carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2- methyl-oxiranyl)-2-oxo- ethylcarbamoyl]-2-difluoromethoxyethyl- carbamoyl}-2- difluoromethoxyethyl)- amideoff-white powder 45 ¹H NMR (300 MHz, CDCl₃): δ (ppm): 8.05 (s, 1H),7.30-7.27 (m, 3H), 7.18 (dd, 2H), 6.79 (d, 1H), 6.76 (d, 1H), 6.63 (d,1H), 6.16 (wt, 1H), 6.10 (wt, 1H), 4.88-4.61 (m, 2H), 4.58 (td, 1H),4.31 (dd, 1H), 4.22 (dd, 1H), 4.01 (td, 1H), 3.89 (dd, 1H), 3.26 (d,1H), 3.24 (dd, 1H), 3.14 (d, 1H), 2.85 (dd, 1H), 2.85 (dd, 1H), 2.68 (s,3H), 1.43 (s, 3H).  5

3-Methyl-isoxazole-5- carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2- methyl-oxiranyl)-2-oxo- ethylcarbamoyl]-2-difluoromethoxyethyl- carbamoyl}-2- difluoromethoxyethyl)- amide whitesolid 75 ¹H NMR (300 MHz, CDCl₃): δ (ppm): 7.87 (s, 1H), 7.31-7.28 (m,3H), 7.18 (dd, 2H), 6.79 (d, 1H), 6.76 (d, 1H), 6.63 (d, 1H), 6.14 (wt,1H), 6.14 (wt, 1H), 4.78-4.55 (m, 2H), 4.55 (td, 1H), 4.29 (dd, 1H),4.19 (dd, 1H), 4.02 (td, 1H), 3.91 (dd, 1H), 3.24 (d, 1H), 3.24 (dd,1H), 3.14 (d, 1H), 2.85 (dd, 1H), 2.78 (dd, 1H), 2.45 (s, 3H), 1.45 (s,3H).  6

Thiazole-5-carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2- oxoethylcarbamoyl]-2- difluoromethoxyethylcarbamoyl}-2- difluoromethoxyethyl)amide off-white yellowish powder 63¹H NMR (300 MHz, CDCl₃): δ (ppm): 9.35 (s, 1H), 7.31-7.27 (m, 4H), 7.18(dd, 2H), 6.92 (d, 1H), 6.79 (d, 1H), 6.66 (d, 1H), 6.21 (wt, 1H), 6.16(wt, 1H), 4.92-4.71 (m, 2H), 4.68 (td, 1H), 4.28 (dd, 1H), 4.19 (dd,1H), 4.02 (td, 1H), 3.95 (dd, 1H), 3.28 (d, 1H), 3.25 (dd, 1H), 3.13 (d,1H), 2.88 (dd, 1H), 2.77 (dd, 1H), 1.43 (s, 3H).  7

Oxazole-5-carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2- oxo-ethylcarbamoyl]-2- difluoromethoxy-ethylcarbamoyl}-2- difluoromethoxyethyl)- amide off-white powder 43 ¹HNMR (300 MHz, CDCl₃): δ (ppm): 8.89 (s, 1H), 7.38-7.25 (m, 4H), 7.15(dd, 2H), 6.88 (d, 1H), 6.77 (d, 1H), 6.63 (d, 1H), 6.18 (wt, 1H), 6.13(wt, 1H), 4.83-4.69 (m, 2H), 4.59 (td, 1H), 4.28 (dd, 1H), 4.23 (dd,1H), 4.05 (td, 1H), 3.98 (dd, 1H), 3.31 (d, 1H), 3.28 (dd, IH), 3.09 (d,1H), 2.95 (dd, 1H), 2.89 (dd, 1H), 1.41 (s, 3H).  8

5-Methyl-thiophene-2- carboxylic acid ((S)-1- {(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2- oxo-ethylcarbamoyl]-2- difluoro-methoxyethylcarbamoyl}- 2-difluoromethoxyethyl)- amide yellow powder 36¹H NMR (300 MHz, CDCl₃): δ (ppm): 7.95 (s, 1H), 7.76 (s, 1H), 7.36- 7.28(m, 3H), 7.21 (dd, 2H), 6.90 (d, 1H), 6.81 (d, 1H), 6.72 (d, 1H), 6.21(wt, 1H), 6.22 (wt, 1H), 4.89-4.68 (m, 2H), 4.63 (td, 1H), 4.25 (dd,1H), 4.14 (dd, 1H), 4.04 (td, 1H), 3.87 (dd, 1H), 3.33 (d, 1H), 3.28(dd, 1H), 3.18 (d, 1H), 2.81 (dd, 1H), 2.77 (dd, 1H), 2.51 (s, 3H). 1.41(s, 3H).  9

5-Methyl-furan-2-carboxylic acid ((S)-1-{(S)-1-[(S)-1- benzyl-2-((R)-2-methyloxiranyl)-2-oxo- ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}- 2-difluoromethoxyethyl)- amide off-whitepowder 69 ¹H NMR (300 MHz, CDCl₃): δ (ppm): 7.73 (s, 1H), 7.74 (s, 1H),7.37- 7.25 (m, 3H), 7.18 (dd, 2H), 6.87 (d, 1H), 6.78 (d, 1H), 6.69 (d,1H), 6.22 (wt, 1H), 6.19 (wt, 1H), 4.93-4.72 (m, 2H), 4.71 (td, 1H),4.29 (dd, 1H), 4.18 (dd, 1H), 4.03 (td, 1H), 3.96 (dd, 1H), 3.41 (d,1H), 3.34 (dd, 1H), 3.21 (d, 1H), 2.99 (dd, 1H), 2.75 (dd, 1H), 2.46 (s,3H). 1.42 (s, 3H). 10

Thiophene-2-carboxylic acid ((S)-1- {(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo ethylcarbamoyl]-2- difluoromethoxy-ethylcarbamoyl}-2- difluoromethoxyethyl)-amide off-white powder 74 ¹HNMR (300 MHz, CDCl₃): δ (ppm): 7.95 (d, 1H), 7.77-158 (m, 2H), 7.38-7.26(m, 3H), 7.19 (dd, 2H), 6.88 (d, 1H), 6.79 (d, 1H), 6.68 (d, 1H), 6.18(wt, 1H), 6.19 (wt, 1H), 4.91-4.72 (m, 2H), 4.58 (td, 1H), 4.17 (dd,1H), 4.11 (dd, 1H), 4.01 (td, 1H), 3.91 (dd, 1H), 3.36 (d, 1H), 3.22(dd, 1H), 3.13 (d, 1H), 2.91 (dd, 1H), 2.68 (dd, 1H), 1.45 (s, 3H). 11

N-[(1S)-2-[[(1S)-2-[[(1S)-1- benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]amino]- 1(difluoromethoxymethyl)-2-oxo-ethyl]amino]-1- (difluoromethoxymethyl)-2-oxo-ethyl]-1H-1,2,4-triazole-5- carboxamide white powder  6 ¹H NMR (300MHz, d₆-DMSO): δ (ppm): 8.58 (d, J = 4 HZ, 1H), 8.49 (d, J = 8 Hz, 1H),7.29-7.16 (m, 6H), 6.61 (d, J = 76 Hz, 1H), 6.60 (d, J = 76 Hz, 1H),4.83-4.76 (m, 1H), 4.63-4.54 (m, 2H), 4.14-4.08 (m, 2H), 3.99-3.85 (m,2H), 3.18 (d, J = 6 Hz, 1H), 2.99-2.91 (m, 2H), 2.73-2.64 (m, 1H), 1.34(s, 3H). 12

N-[(1S)-1- (difluoromethoxymethyl)-2- [[(1S)-1-(difluoromethoxymethyl)-2- [[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]- amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]-2-methylthiazole-5- carboxamide white powder 75 ¹H NMR (300MHz, d₆-DMSO): δ (ppm): 8.88 (d, J = 4 Hz, 1H), 8.50 (d, J = 4 Hz, 1H),8.34-8.28 (m, 2H), 6.65 (t, J = 76 Hz, 1H), 6.61 (t, J = 76 Hz, 1H),4.83-4.74 (m, 1H), 4.58-4.49 (m, 1H), 4.40-4.31 (m, 1H), 4.15- 4.08 (m,1H), 4.05-3.88 (m, 3H), 3.12 (d, J = 4 Hz, 1H), 2.98 (d, J = 4 Hz, 1H),2.65 (s, 3H), 1.67-1.55 (m, 1H), 1.38 (s, 3H), 1.35-1.22 (m, 2H), 0.86(d, J = 6 Hz, 3H), 0.81 (d, J = 6 Hz, 3H). 13

Pyridine-2-carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo- ethylcarbamoyl]-2- difluoromethoxy-ethylcarbamoyl}-2- difluoromethoxyethyl)-amide white powder 86 ¹H NMR(300 MHz, d₆-DMSO): δ (ppm): 8.39 (d, 1H), 7.45-7.35 (m, 2H), 7.31-7.14(m, 6H), 6.59 (wt, J = 75 Hz, 1H), 6.57 (wt, J = 76 Hz, 1H), 4.85-4.78(m, 1H), 4.71-4.56 (m, 2H), 4.12-4.05 (m, 2H), 4.01-3.87 (m, 2H),3.19-3.14 (m, 1H), 3.02-2.94 (m, 2H), 2.68-2.58 (m, 1H), 1.36 (s, 3H).14

N-((S)-1-{(S)-1-[(S)-1-Benzyl- 2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2- difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)- nicotinamide white powder 77 ¹H NMR (300 MHz,d₆-DMSO): δ (ppm): 8.33 (s, 1H), 8.28 (dd, 1H), 7.38-7.29 (m, 2H),7.29-7.17 (m, 5H), 6.62 (wt, J = 75 Hz, 1H), 6.59 (wt, J = 76 Hz, 1H),4.78-4.67 (m, 1H), 4.83-4.59 (m, 2H), 4.15-4.03 (m, 2H), 3.98-3.83 (m,2H), 3.21-3.15 (m, 1H), 2.99-2.91 (m, 2H), 2.70-2.56 (m, 1H), 1.35 (s,3H). 15

Pyridine-2-carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo- ethylcarbamoyl]-2- difluoromethoxy-ethylcarbamoyl}-2- difluoromethoxy-ethyl)-amide white yellowish powder61 ¹H NMR (300 MHz, d₆-DMSO): δ (ppm): 8.65 (s, 1H), 8.41-8.35 (m, 2H),7.27-7.16 (m, 5H), 6.61 (wt, J = 75 Hz, 1H), 6.58 (wt, J = 76 Hz, 1H),4.81-4.69 (m, 1H), 4.82-4.57 (m, 2H), 4.21-4.04 (m, 2H), 3.99-3.79 (m,2H), 3.25-3.18 (m, 1H), 2.99-2.91 (m, 2H), 2.69-2.54 (m, 1H), 1.37 (s,3H). 16

N-[(1S)-2-[[(1S)-2-[[(1S)-1- benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]amino]-1- (difluoromethoxymethyl)-2-oxo-ethyl]amino]-1- (difluoromethoxymethyl)-2-oxo-ethyl]-pyrimidine-2-carboxamide white yellowish powder 56 ¹H NMR (300MHz, d₆-DMSO): δ (ppm): 8.55-7.58 (m, 2H), 7.55-745 (m, 1H), 7.29-7.18(m, 5H), 6.59 (wt, J = 75 Hz, 1H), 6.57 (wt, J = 76 Hz, 1H), 4.78-4.65(m, 1H), 4.80-4.61 (m, 2H), 4.17-4.01 (m, 2H), 4.02- 3.85 (m, 2H),3.23-3.17 (m, 1H), 2.98-2.87 (m, 2H), 2.70-2.55 (m, 1H), 1.35 (s, 3H).17

[1,2,4]Triazine-3-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl- oxiranyl)-2-oxo- ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}- 2-difluoromethoxy-ethyl)- amide whitesolid 51 ¹H NMR (300 MHz, d₆-DMSO): δ (ppm): 9.61 (dd, 1H), 932 (dd,1H), 7.32-7.15 (m, 5H), 6.60 (wt, J = 75 Hz, 1H), 6.58 (wt, J = 76 Hz,1H), 4.71-4.61 (m, 1H), 4.76-4.59 (m, 2H), 4.19-3.99 (m, 2H), 4.03-3.88(m, 2H), 3.25-3.16 (m, 1H), 2.97-2.85 (m, 2H), 2.68-2.53 (m, 1H), 1.37(s, 3H). 18

Pyrimidine-4-carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo- ethylcarbamoyl]-2- difluoromethoxy-ethylcarbamoyl}-2- difluoromethoxyethyl)-amide white solid 39 ¹H NMR(300 MHz, d₆-DMSO): δ (ppm): 9.73 (s, 1H), 7.93 (dd, 1H), 7.68 (dd, 1H),7.32-7.15 (m, 5H), 6.60 (wt, J = 75 Hz, 1H), 6.58 (wt, J = 76 Hz, 1H),4.75-4.61 (m, 1H), 4.83-4.59 (m, 2H), 4.21-4.03 (m, 2H), 4.01-3.84 (m,2H), 3.19-3.13 (m, 1H), 3.01-2.89 (m, 2H), 2.67-2.51 (m, 1H), 1.37 (s,3H). 19

2-Methyl-thiazole-5- carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl- oxiranyl)-2-oxo- ethylcarbamoyl]-3-methylbutylcarbamoyl}-2- difluoromethoxyethyl)-amide white yellowishsolid 48 ¹H NMR (300 MHz, d₆-DMSO): δ (ppm): 8.77 (s, 1H), 7.31-7.16 (m,3H), 7.11 (dd, 2H), 6.71 (wd, 1H), 6.63 (d, 1H), 6.41 (t, 1H), 6.17 (t,J = 75 Hz, 1H), 5.21 (br. s, 1H), 4.81-4.78 (m, 1H), 4.53 (td, 1H),4.41-4.37 (m, 1H), 4.23-4.05 (m, 2H), 4.01 (dd, 1H), 3.97-3.90 (m, 1H),3.25 (s, 3H), 3.21 (d, 1H), 3.16-3.13 (m, 1H), 2.79 (d, 1H), 2.81-7.65(m, 1H), 1.79-1.68 (m, 1H), 1.47 (s, 3H), 0.97-0.89 (m, 6H). 20

2-Methyl-thiazole-5-carboxylic acid ((S)-2-difluoromethoxy-1-{(S)-3-methyl-1-[(S)-3-methyl- 1-((R)-2- methyloxiranecarbonyl)-butylcarbamoyl]- butylcarbamoyl}-ethyl)-amide white yellowish solid 67¹H NMR (300 MHz, d₆-DMSO): δ (ppm): 8.65 (s, 1H), 6.98 (wd, 1H), 6.83(wd, 1H), 6.61-6.53 (m, 1H), 6.17 (t, J = 75 Hz, 1H), 6.07 (br. s, 1H),4.79-4.68 (m, 1H), 4.61-4.55 (m, 1H), 4.26-4.15 (m, 1H), 4.13-4.03 (m,2H), 3.98-3.86 (m, 1H), 3.81 (dd, 1H), 3.21 (s, 3H) 3.27 (d, 1H), 3.12(dd, 1H), 2.81 (d, 1H), 2.78-2.75 (m, 1H), 1.71-1.67 (m, 2H), 1.47 (s,3H), 0.97-0.89 (m, 12H). 21

2-Methyl-thiazole-5-carboxylic acid ((S)-1-{(S)-2-difluoromethoxy-1-[(S)-3-methyl-1-((R)-2- methyloxiranecarbonyl)- butylcarbamoyl]-ethylcarbamoyl}-3- methylbutyl)-amide white yellowish solid 34 ¹H NMR(300 MHz, d₆-DMSO): δ (ppm): 8.61 (s, 1H), 6.81-6.78 (m, 2H), 6.68-6.61(m, 1H), 6.16 (t, J = 75 Hz, 1H), 5.99 (br. s, 1H), 4.79-4.59 (m, 2H),4.26-4.06 (m, 3H), 3.99-3.89 (m, 1H), 3.76 (dd, 1H), 3.27 (d, 1H), 3.18(s, 3H), 3.15 (dd, 1H), 2.93 (d, 1H), 2.75-2.71 (m, 1H), 1.681.64 (m,2H), 1.48 (s, 3H), 0.98-0.90 (m, 12H). 22

2-Methyl-thiazole-5-carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl- oxiranyl)-2-oxo- ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}- 3-methylbutyl)-amide white yellowishsolid 34 ¹H NMR (300 MHz, d₆-DMSO): δ (ppm): 8.65 (s, 1H), 7.28-7.17 (m,3H), 7.09 (dd, 2H), 7.01-6.71 (m, 1H), 6.65 (d, 1H), 6.38 (t, 1H), 6.15(t, J = 75 Hz, 1H), 5.98 (br. s, 1H), 4.75-4.67 (m, 1H), 4.45 (td, 1H),4.45-4.36 (m, 1H), 4.30-4.05 (m, 2H), 3.98 (dd, 1H), 3.95-3.88 (m, 1H),3.19 (s, 3H), 3.17 (d, 1H), 3.15-3.08 (m, 1H), 2.81 (d, 1H), 2.77-7.60(m, 1H), 1.81-1.72 (m, 1H), 1.46 (s, 3H), 0.98-0.87 (m, 6H). 23

2-Methyl-thiazole-5-carboxylic acid ((S)-1-{(S)-2-difluoromethoxy-1-[(S)-3- methyl-1-((R)-2-methyl- oxiranecarbonyl)-butylcarbamoyl]-ethylcarbamoyl}- 2-phenylethyl)-amide yellow solid 28 ¹HNMR (300 MHz, d₆-DMSO): δ (ppm): 8.69 (s, 1H), 7.32-7.16 (m, 3H), 7.13(dd, 2H), 7.11-6.91 (m, 1H), 6.72 (d, 1H), 6.48 (t, 1H), 6.17 (t, J = 75Hz, 1H), 6.08 (br. s, 1H), 4.75-4.67 (m, 1H), 4.45 (td, 1H), 4.45-4.36(m, 1H), 4.30-4.05 (m, 2H), 3.98 (dd, 1H), 4.01-3.89 (m, 1H), 3.21 (s,3H), 3.19 (d, 1H), 3.17-3.11 (m, 1H), 2.78 (d, 1H), 2.76-7.62 (m, 1H),1.85-1.77 (m, 1H), 1.45 (s, 3H), 0.97-0.86 (m, 6H). 24

2-Methyl-thiazole-5- carboxylic acid ((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl- oxiranyl)-2-oxo- ethy!carbamoyl]-2-difluoromethoxyethylcarbamoyl}- 2-phenylethyl)-amide yellow pale solid49 ¹H NMR (400 MHz, CDCl₃): δ (ppm): δ (ppm): 8.45 (s, 1H), 7.35-7.07(m, 10H), 6.81-6.76 (m, 1H), 6.62-6.57 (m, 1H), 6.19 (t, J = 72 Hz, 1H),4.78-4.67 m, 1H), 4.63-4.52 (m, 2H), 4.28-4.19 (m, 1H), 4.03-3.93 (m, 1H), 3.55 (br. s, 2H), .53-2.39 (m, 4H), 1.46 (s, 3H).

TABLE 6 Compound Yield # Structure Nomenclature Appearance (%) XVII(b)

benzyl (2S)-3- (difluoromethoxy)- 2-[[(2S)-3- (difluoromethoxy)- 2-[(2-morpholinoacetyl)amino] propanoyl]amino]propanoate white solid 84 ¹H NMR(400 MHz, CDCl₃): δ (ppm): 7.89 (m, 1H), 7.41-7.30 (m 5H), 7.04 (m, 1H),6.22 (t, J = 74 Hz, 1H), 6.13(t, J = 74 Hz, 1H), 5.22 (s, 2H), 4.84-4.78(m, 1H), 4.77-4.72 (m, 1H), 4.32-4.27 (m, 2H), 4.21- 4.15 (m, 1H),4.07-4.00 (m, 1H), 3.76-3.69 (m, 4H), 3.07 (s, 2H), 2.68- 2.52 (m, 4H).XVII(c)

benzyl(2S)-2- [[(2S)-3-(difluoro- methoxy)-2-[(2- morpholinoacetyl)-amino]- propanoyl]amino]- 4- methylpentanoate off-white powder 89 ¹H NMR(400 MHz, CDCl₃): δ (ppm): 7.85 (m, 1H), 7.40-7.30 (m, 5H), 6.66 (m,1H), 6.20 (t, J = 74 Hz, 1H), 5.20-5.12 (m, 2H), 4.72-4.58 (m, 2H),4.26-4.22 (m, 1H), 4.03-3.97 (m, 1H), 3.75-3.67 (m, 4H), 3.06 (s, 2H),2.55-2.50 (m, 4H), 1.72-1.62 (m, 1H), 0.96-0.85 (m, 6H). XVII(d)

benzyl (2S)- 3(difluoromethoxy)-2- [[(2S)-2-[(2- morpholinoacetyl)amino]-3-phenyl- propanoyl]amino]- propanoate off-white powder 76 ¹H NMR(400 MHz, CDCl₃): δ (ppm): 7.81 (m, 1H), 7.41-6.95 (m 10 H), 6.17 (t, J= 74 Hz, 1H), 5.21-5.13 (m, 2H), 4.90-4.83 (m, 1H), 4.72-4.64 (m, 1H),4.31-4.25 (m, 1H), 401-3.93 (m, 1H), 3.73-3.61 (m, 4H), 3.91- 2.49 (m,4H), 2.51-2.43 (m, 4H). XVII(e)

benzyl (2S)-3- (difluoromethoxy)-2- [[(2S)-4-methyl-2-[(2-morpholinoacetyl)amino] pentanoyl]amino]propanoate off-white powder 87

TABLE 7 Compound Yield # Structure Nomenclature Appearance (%) XVIII(b)

(2S)-3- (difluoromethoxy)-2- [[(2S)-3- (difluoromethoxy)-2-[(2-morpholino- acetyl)amino] propanoyl]amino]- propanoic acid whitesolid 95 ¹H NMR (300 MHz, CDCl₃): δ (ppm): 7.89 (m, 1H), 7.41-7.30 (m,5H), 7.04 (m, 1H), 6.22 (t, J = 74 Hz, 1H), 6.13 (t, J = 74 Hz, 1H),5.22 (s, 2H), 4.84-4.78 (m, 1H), 4.77-4.72 (m, 1H), 4.32-4.27 (m, 2H),4.21- 4.15 (m, 1H), 4.07-4.00 (m, 1H), 3.76-3.69 (m, 4H), 3.07 (s, 2H),2.68-2.52 (m, 4H). XVIII(c)

(2S)-2-[[(2S)-3- (difluoromethoxy)- 2-[(2- morpholinoacetyl) amino]-propanoyl]amino]- 4-methylpentanoic acid off-white sticky solid 99 ¹HNMR (300 MHz, CDCl₃): δ (ppm): 7.85 (m, 1H), 7.40-7.30 (m, 5H), 6.66 (m,1H), 6.20 (t, J = 74 Hz, 1H), 5.20-5.12 (m, 2H), 4.72-4.58 (m, 2H),4.26-4.22 (m, 1H), 4.03-3.97 (m, 1H), 3.75-3.67 (m, 4H), 3.06 (s, 2H),2.55-2.50 (m, 4H), 1.72-1.62 (m, 1H), 0.96-0.85 (m, 6H).

TABLE 8 Example Yield # Structure Nomenclature Appearance (%) 26

(S)-N-{(S)-1-[(S)-1- Benzyl-2-((R)-2-methyl- oxiranyl)-2-oxo-ethylcarbamoyl]-2- difluoromethoxyethyl}-3- difluoromethoxy-2-(2-morpholin-4-yl- acetylamino)-propionamide white solid 53 ¹H NMR (400MHz, CDCl₃): δ (ppm): 7.94 (m, 1H), 7.32-7.12 (m, 5H), 6.87 (m, 1H),6.70 (m, 1H), 6.22 (t, J = 74 Hz, 1H), 6.12 (t, J = 74 Hz, 1H),4.88-4.78 (m, 1H), 4.66-4.55 (m, 1H), 4.32-4.26 (m, 1H), 4.23-4.14 (m,1H), 4.08-4.02 (m, 1H), 3.92-3.88 (m, 1H), 3.77-3.68 (m, 4H), 3.28- 2.80(m, 5H), 2.60-2.51 (m, 4H), 1.51 (s, 3H). 27

(2S)-N-[(1S)-1-benzyl-2- [(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]-2-[[(2S)-3- (difluoromethoxy)-2-[(2-morpholinoacetyl)amino] propanoyl]amino]-4- methylpentanamide off-whitesolid 47 ¹H NMR (400 MHz, CDCl₃): δ (ppm): 7.85 (m, 1H), 7.38-7.12 (m,5H), 6.82-6.78 (m, 1H), 6.24 (t, J = 74 Hz, 1H), 6.13-6.11 (m, 1H),4.71-4.58 (m, 3H), 4.42-4.35 (m, 1H), 4.15-4.05 (m, 1H), 3.83-3.75 (m,4H), 3.33- 2.95 (m, 5H), 2.60-2.55 (m, 4H), 2.22 (s, 3H), 1.61-1.42 (m,3H), 0.98- 0.87 (m, 6H). 28

(2S)-2-[[(2S)-3- (difluoromethoxy)-2-[(2- morpholino-acetyl)amino]propa-noyl]amino]-4- methyl-N-[(1S)-3-methyl- 1-[(2R)-2-methyloxirane-2-carbonyl] butyl]pentanamide pale solid 71 ¹H NMR (400 MHz, CDCl₃): δ(ppm): 7.84 (m, 1H), 6.59 (m, 1H), 6.26 (t, J = 74 Hz, 1H), 6.22 (m,1H), 4.70-4.64 (m, 1H), 4.61-4.55 (m, 1H), 4.43-4.36 (m, 1H), 4.29-4.02(m, 1H), 3.75-3.71 (m, 4H), 3.28-3.25 (m, 1H), 3.07 (s, 2H), 2.91-2.87(m, 1H), 2.57-2.53 (m, 4H), 1.68-1.50 (m, 4H), 1.51 (s, 3H), 1.31-1.22(m, 2H), 0.97-0.89 (m, 12H). 29

(2S)-N-[(1S)-1-benzyl-2- [(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]-2-[[(2S)-3- (difluoromethoxy)-2-[(2-morpholinoacetyl)amino] propanoyl]amino]-3-(1- methylcyclohexa-1,3,5-trien-1-yl)propanamide white powder 63 ¹H NMR (400 MHz, CDCl₃): δ (ppm):δ 7.74 (m, 1H), 7.32-6.98 (m, 10H), 6.70 (m, 1H), 6.59 (m, 1H), 6.18 (t,J = 72 Hz, 1H), 4.81-4.68 m, 1H), 4.61-4.51 (m, 2H), 4.23 = 4.17 (m,1H), 3.99-3.95 (m, 1H), 3.68 (br. s, 2H), 3.10-2.90 (m, 6H), 2.80-2.59(m, 2H), 2.53-2.39 (m, 4H), 1.48 (s, 3H). 30

(S)-4-Methyl-2-(2- morpholin-4-yl-acetylamino)- pentanoic acid {(S)-2-difluoromethoxy-1-[(S)-3- methyl-1-((R)-2-methyl- oxiranecarbonyl)-butylcarbamoyl]-ethyl}- amide off-white solid 34 ¹H NMR (400 MHz,CDCl₃): δ (ppm): 7.88-7.76 (m, 1H), 6.63-6.59 (m, 1H), 6.29 (t, J = 75Hz, 1H), 6.34 (m, 1H), 4.81-4.75 (m, 1H), 4.70-4.63 (m, 1H), 4.47-4.4(m, 1H), 4.32-4.05 (m, 1H), 3.81-3.74 (m, 4H), 3.36- 3.26 (m, 1H), 3.11(s, 2H), 3.01-2.95 (m, 1H), 2.66-2.61 (m, 4H), 1.73- 1.65 (m, 4H), 1.52(s, 3H), 1.42-1.36 (m, 2H), 0.99-0.91 (m, 12H). 31

(S)-4-Methyl-2-(2-morpholin-4- yl-acetylamino)-pentanoic acid{(S)-1-[(S)-1-benzyl-2-((R)-2- methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2- difluoro- methoxyethyl}-amide off-white solid72 ¹H NMR (400 MHz, CDCl₃): δ (ppm): 8.01 (m, 1H), 7.02 (m, 1H), 6.79(m, 1H), 6.41 (t, J = 74 Hz, 1H), 6.35 (t, J = 74 Hz, 1H), 4.74-4.68 (m,3H), 4.88-4.24 (m, 2H), 4.14-4.08 (m, 1H), 3.97-3.89 (m, 1H), 3.76-3.68(m, 4H), 3.22 (d, J = 4 Hz, 1H), 2.90 (d, J = 4 Hz, 1H), 2.58-2.53 (m,4H), 1.63-1.50 (m, 2H), 1.51 (s, 3H), 1.36-1.26 (m, 1H), 0.96-0.91 (m,6H). 32

(2S)-N-[(1S)-2-[[(1S)-1-benzyl-2- [(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]amino]- 1(difluoromethoxymethyl)-2-oxo-ethyl]-2-[(2-morpholino- acetyl)amino]-3-phenyl- propanamide off-whitepowder 61 ¹H NMR (400 MHz, CDCl₃): δ (ppm): 7.82 (m, 1H), 7.42-7.01 (m,10H), 6.77-6.68 (m, 1H), 6.65-6.58 (m, 1H), 6.18 (t, J = 74 Hz, 1H),4.86-4.72 (m, 1H), 4.72-4.60 (m, 2H), 4.23-4.21-4.16 (m, 1H), 402-3.98(m, 1H), 3.71 (br. s, 2H), 3.14-2.95 (m, 6H), 2.82-2.69 (m, 2H),2.62-2.47 (m, 4H), 1.49 (s, 3H). 33

(2S)-3-(difluoromethoxy)-N- [(1S)-1- (difluoromethoxymethyl)-2-[[(1S)-3-methyl-1-[(2R)-2- methyloxirane-2- carbonyl]butyl]amino]-2-oxo-ethyl]-2-[(2- morpholinoacetyl)amino] propanamide off-white powder 71NMR (CDCl₃, 400 MHz): δ (ppm): 7.93 (m, 1H), 6.95 (m, 1H), 6.58 (m, 1H),6.29 (t, J = 74 Hz, 1H), 6.22 (t, J = 74 Hz, 1H), 4.74-4.68 (m, 3H),4.88-4.24 (m, 2H), 4.14-4.08 (m, 1H), 3.97-3.89 (m, 1H), 3.76-3.68 (m,4H), 3.22 (d, J = 4 Hz, 1H), 2.90 (d, J = 4 Hz, 1H), 2.58-2.53 (m, 4H),1.63-1.50 (m, 2H), 1.51 (s, 3H), 1.36-1.26 (m, 1H), 0.96-0.91 (m, 6H).

TABLE 9 Cell line OCI-AML-2 KMS-11 Ex- IC₅₀ (nM)* am- CT-L CT-L pleproteasome proteasome # Cell Viability activity Cell Viability activity1 108.7 ± 25.31 39.17 ± 2.121 30.90 ± 10.71 29.62 ± 3.69  25 55.60 ±19.20 153.9 ± 14.81 39.55 ± 7.45  172.9 ± 14.15 27 400.6 ± 275.4 599.9 ±57.47 249.6 ± 25.89 742.5 ± 83.71 28 131.6 ± 87.55 556.1 ± 122.9 100.3 ±18.69 575.1 ± 62.72 26 223.2 ± 10.34 358.5 ± 176.8 99.67 ± 17.73 174.1 ±434.5 33 140.2 ± 53.47 598.8 ± 77.65 46.71 ± 9.89  703.8 ± 173   2975.86 ± 14.97 131.7 ± 10.38  60.4 ± 11.18 135.3 ± 12.3  *Unlessotherwise indicated, all experiments have been performed independentlyat least twice, and results are presented as the mean ± standarddeviation.

TABLE 10* Example # chymotrypsin-like (CT-L) Trypsin-like (T-L)Caspase-like (C-L) (Dose) 0 30 min 24 hours 0 30 min 24 hrs 0 30 min 24hrs Vehicle 100% 98% 101%  100% 100% 100% 100% 100% 100%  1 (50 mg) 100%27% 22% 100% 100% 100% 100% 100% 100% 26 (60 mg) 100% 33% 27% 100% 100%100% 100% 100% 100% *Data are presented as mean residual activity (SEM)relative to vehicle treated controls.

TABLE 11 Panel/Cell Line Log₁₀GI₅₀ Log₁₀TGI₅₀ Log₁₀LC₅₀ LeukemiaCCRF-CEM −7.26 >−4.00 >−4.00 HL-60(TB) −6.56 >−4.00 >−4.00 K-562−6.50 >−4.00 >−4.00 MOLT-4 −7.37 >−4.00 >−4.00 RPMI-8226 −7.40−4.86 >−4.00 SR −7.30 >−4.00 >−4.00 Non-Small Cell Lung Cancer A549/ATCC−6.41 >−4.00 >−4.00 EKVX −6.22 >−4.00 >−4.00 HOP-62 −6.41 >−4.00 >−4.00HOP-92 −6.23 −5.40 −4.39 NCI-H226 −7.44 −6.84 — NCI-H23 −6.85 −5.92−5.27 NCI-H322M −5.54 −4.74 −4.23 NCI-H460 −6.48 −5.84 −5.12 NCI-H522−6.86 −6.15 −4.15 Colon Cancer COLO 205 −6.22 −4.85 >−4.00 HCC-2998−6.74 −6.45 −6.15 HCT-116 −7.32 −6.71 −6.17 HCT-15 −5.65 −4.93 −4.16HT29 −7.29 −6.22 −4.32 KM12 −6.88 −6.49 −6.10 SW-620 −7.39 −5.95 −4.40CNS Cancer SF-268 −6.98 −5.90 >−4.00 SF-295 −7.17 −6.24 −4.88 SF-539−7.15 −6.44 −4.27 SNB-19 −6.49 >−4.00 >−4.00 SNB-75 −6.81 −6.24 >−4.00U251 −6.55 −4.94 >−4.00 Melanoma LOX IMVI −6.96 −6.56 −6.16 MALME-3M−7.30 −6.38 >−4.00 M14 −6.86 −6.24 −4.35 MDA-MB-435 −7.43 −6.74 >−4.00SK-MEL-28 −6.85 −6.12 −4.69 SK-MEL-5 −7.15 −6.34 −5.47 UACC-257 −6.87−6.20 >−4.00 UACC-62 −6.68 −5.78 −4.95 Ovarian Cancer OVCAR-3 −7.46−6.90 −6.30 OVCAR-4 −6.29 >−4.00 >−4.00 OVCAR-5 −6.18 −5.30 −4.17OVCAR-8 −5.80 >−4.00 >−4.00 NCI/ADR-RES −5.11 −4.23 >−4.00 SK-OV-3−6.06 >−4.00 >−4.00 Renal Cancer 786-0 −6.43 −4.62 >−4.00 A498 −8.00−6.38 −4.88 ACHN −6.53 −4.81 >−4.00 CAKI-1 −6.40 −5.28 >−4.00 RXF 393−6.79 −6.41 −6.02 SN12C −6.54 −5.29 −4.03 TK-10 −6.71 −6.06 — UO-31−5.84 −5.32 −4.59 Prostate Cancer PC-3 −6.48 −4.99 >−4.00 DU-145 −6.58−5.64 −5.02 Breast Cancer MCF7 −7.35 −4.62 >−4.00 MDA-MB- −6.66 −6.01−4.73 231/ATCC HS 578T −7.33 −5.44 >−4.00 BT-549 −7.49 −6.87 −5.74 T-47D−6.59 >−4.00 — MDA-MB-468 −6.75 −6.32 —

TABLE 12 Panel/Cell Line Log₁₀GI₅₀ Log₁₀TGI₅₀ Log₁₀LC₅₀ LeukemiaHL-60(TB) −7.45 −6.35 >−4.00 K-562 −7.41 >−4.00 >−4.00 MOLT-4 −7.69−7.11 >−4.00 RPMI-8226 −7.52 −7.04 >−4.00 SR −7.71 >−4.00 >−4.00Non-Small Cell Lung Cancer A549/ATCC −7.41 −6.13 >−4.00 HOP-62 −7.75−7.42 −7.09 HOP-92 −7.65 −7.16 −6.35 NCI-H226 −7.77 −7.43 −7.10 NCI-H23−7.62 −7.13 −5.64 NCI-H322M −7.10 −6.33 >−4.00 NCI-H460 −7.21 −6.43−4.13 NCI-H522 −7.67 −7.19 >−4.00 Colon Cancer COLO 205 −7.39 −6.76−6.21 HCC-2998 −7.74 −7.47 −7.20 HCT-116 −7.70 −7.30 −6.55 HCT-15−6.47 >−4.00 >−4.00 HT29 −7.45 −5.84 >−4.00 KM12 −7.72 −7.39 −7.06SW-620 −7.41 −5.93 >−4.00 CNS Cancer SF-268 −7.60 −7.14 >−4.00 SF-295−7.68 −7.26 −6.49 SF-539 −7.63 −7.26 −6.48 SNB-19 −7.23 >−4.00 >−4.00SNB-75 −7.71 −7.24 −6.35 U251 −7.44 −6.75 >−4.00 Melanoma LOX IMVI −7.73−7.42 −7.10 MALME-3M −7.51 −6.64 >−4.00 M14 −7.48 −6.71 >−4.00MDA-MB-435 −7.75 −7.42 −7.10 SK-MEL-2 −7.54 −7.03 −5.46 SK-MEL-28 −7.38−6.69 −4.82 SK-MEL-5 −7.60 −7.17 −6.49 UACC-257 −7.18 −6.32 >−4.00UACC-62 −7.35 −6.63 −4.58 Ovarian Cancer IGROV1 −7.43 −6.38 >−4.00OVCAR-3 −7.66 −7.33 −6.97 OVCAR-4 −7.50 −6.75 >−4.00 OVCAR-5 −7.36−6.44 >−4.00 OVCAR-8 −7.32 −6.41 >−4.00 NCI/ADR-RES −5.82 >−4.00 >−4.00SK-OV-3 −7.30 −6.60 — Renal Cancer 786-0 −7.20 −6.49 −5.44 A498 −7.61−7.03 −6.34 ACHN −7.01 >−4.00 >−4.00 CAKI-1 −6.72 −6.09 >−4.00 RXF 393−7.64 −7.25 −6.70 SN12C −7.39 −6.67 −5.15 TK-10 −7.49 −6.07 >−4.00 UO-31−6.62 −5.95 −5.17 Prostate Cancer PC-3 −7.45 −6.80 −5.14 DU-145 −7.27−5.32 >−4.00 Breast Cancer MCF7 −7.53 −4.89 >−4.00 MDA-MB- −7.52 −6.80−4.21 231/ATCC HS 578T −7.54 −6.24 >−4.00 BT-549 −7.73 −7.39 −7.05 T-47D−7.78 −7.46 — MDA-MB-468 −7.54 −6.96 >−4.00

TABLE 13 Panel/Cell Line Log₁₀GI₅₀ Log₁₀TGI₅₀ Log₁₀LC₅₀ LeukemiaHL-60(TB) −7.45 −6.35 >−4.00 K-562 −7.41 >−4.00 >−4.00 MOLT-4 −7.69−7.11 >−4.00 RPMI-8226 −7.52 −7.04 >−4.00 SR −7.71 >−4.00 >−4.00Non-Small Cell Lung Cancer A549/ATCC −7.41 −6.13 >−4.00 HOP-62 −7.75−7.42 −7.09 HOP-92 −7.65 −7.16 −6.35 NCI-H226 −7.77 −7.43 −7.10 NCI-H23−7.62 −7.13 −5.64 NCI-H322M −7.10 −6.33 >−4.00 NCI-H460 −7.21 −6.43−4.13 NCI-H522 −7.67 −7.19 >−4.00 Colon Cancer COLO 205 −7.39 −6.76−6.21 HCC-2998 −7.74 −7.47 −7.20 HCT-116 −7.70 −7.30 −6.55 HCT-15−6.47 >−4.00 >−4.00 HT29 −7.45 −5.84 >−4.00 KM12 −7.72 −7.39 −7.06SW-620 −7.41 −5.93 >−4.00 CNS Cancer SF-268 −7.60 −7.14 >−4.00 SF-295−7.68 −7.26 −6.49 SF-539 −7.63 −7.26 −6.48 SNB-19 −7.23 >−4.00 >−4.00SNB-75 −7.71 −7.24 −6.35 U251 −7.44 −6.75 >−4.00 Melanoma LOX IMVI −7.73−7.42 −7.10 MALME-3M −7.51 −6.64 >−4.00 M14 −7.48 −6.71 >−4.00MDA-MB-435 −7.75 −7.42 −7.10 SK-MEL-2 −7.54 −7.03 −5.46 SK-MEL-28 −7.38−6.69 −4.82 SK-MEL-5 −7.60 −7.17 −6.49 UACC-257 −7.18 −6.32 >−4.00UACC-62 −7.35 −6.63 −4.58 Ovarian Cancer IGROV1 −7.43 −6.38 >−4.00OVCAR-3 −7.66 −7.33 −6.97 OVCAR-4 −7.50 −6.75 >−4.00 OVCAR-5 −7.36−6.44 >−4.00 OVCAR-8 −7.32 −6.41 >−4.00 NCI/ADR-RES −5.82 >−4.00 >−4.00SK-OV-3 −7.30 −6.60 Renal Cancer 786-0 −7.20 −6.49 −5.44 A498 −7.61−7.03 −6.34 ACHN −7.01 >−4.00 >−4.00 CAKI-1 −6.72 −6.09 >−4.00 RXF 393−7.64 −7.25 −6.70 SN12C −7.39 −6.67 −5.15 TK-10 −7.49 −6.07 >−4.00 UO-31−6.62 −5.95 −5.17 Prostate Cancer PC-3 −7.45 −6.80 −5.14 DU-145 −7.27−5.32 >−4.00 Breast Cancer MCF7 −7.53 −4.89 >−4.00 MDA-MB- −7.52 −6.80−4.21 231/ATCC HS 578T −7.54 −6.24 >−4.00 BT-549 −7.73 −7.39 −7.05 T-47D−7.78 −7.46 — MDA-MB-468 −7.54 −6.96 >−4.00

TABLE 14 Panel/Cell Line Log₁₀GI₅₀ Log₁₀TGI₅₀ Log₁₀LC₅₀ LeukemiaCCRF-CEM −7.62 >−4.00 >−4.00 K-562 −7.00 >−4.00 >−4.00 MOLT-4 −7.54−7.05 >−4.00 RPMI-8226 −7.40 −6.43 >−4.00 SR −7.69 −4.36 >−4.00Non-Small Cell Lung Cancer A549/ATCC −6.68 >−4.00 >−4.00 HOP-62 −7.31−6.53 −4.32 HOP-92 −7.18 −6.55 −6.03 NCI-H226 −7.64 −7.24 −6.51 NCI-H23−7.21 −5.55 >−4.00 NCI-H322M −6.27 −5.52 −4.18 NCI-H460 −6.49−5.87 >−4.00 NCI-H522 −6.90 −6.17 >−4.00 Colon Cancer COLO 205 −6.90−6.32 −5.34 HCC-2998 −6.80 −6.50 −6.21 HCT-116 −7.46 −5.91 >−4.00 HCT-15−6.20 >−4.00 >−4.00 HT29 −7.31 −4.77 >−4.00 KM12 −7.35 −6.77 −6.27SW-620 −7.40 −4.92 >−4.00 CNS Cancer SF-268 −7.27 −6.50 >−4.00 SF-295−7.19 −6.55 −5.94 SF-539 −7.39 −6.76 −4.49 SNB-19 −6.51 >−4.00 >−4.00SNB-75 −6.83 −6.41 −5.96 U251 −6.98 −5.70 >−4.00 Melanoma LOX IMVI −7.50−6.90 −6.35 MALME-3M −6.69 −6.15 >−4.00 M14 −7.21 −5.85 >−4.00MDA-MB-435 −7.63 −7.17 — SK-MEL-2 −7.19 −6.02 >−4.00 SK-MEL-28 −7.13−6.34 >−4.00 SK-MEL-5 −7.22 −6.66 −6.20 UACC-257 −6.81 −6.00 >−4.00UACC-62 −7.00 −6.37 >−4.00 Ovarian Cancer IGROV1 −6.67 >−4.00 >−4.00OVCAR-3 −7.35 −6.71 −5.66 OVCAR-4 −6.98 >−4.00 — OVCAR-5 −6.65−5.58 >−4.00 OVCAR-8 −6.59 >−4.00 >−4.00 NCI/ADR-RES −5.58 >−4.00 >−4.00SK-OV-3 −6.46 −5.78 >−4.00 Renal Cancer 786-0 −6.55 −5.96 −4.87 A498−6.68 −6.11 −5.47 ACHN −6.59 >−4.00 >−4.00 CAKI-1 −6.56 −5.94 >−4.00 RXF393 −7.20 −6.70 −6.31 SN12C −6.92 −6.38 −4.39 TK-10 −6.55 −5.10 >−4.00UO-31 −6.46 −5.71 −4.62 Prostate Cancer PC-3 −7.04 −6.40 >−4.00 DU-145−7.00 −5.05 −4.09 Breast Cancer MCF7 −7.38 >−4.00 >−4.00 MDA-MB- −7.04−6.27 −4.44 231/ATCC HS 578T −7.07 >−4.00 >−4.00 BT-549 −7.26 −6.59−4.94 T-47D −7.16 −6.62 — MDA-MB-468 −6.67 −6.10 >−4.00

1. A compound of Formula I, or a pharmaceutically acceptable salt orsolvate thereof:

wherein: R¹ is selected from the group consisting of C₁₋₁₀alkyl,C₂₋₁₀alkenyl, C₂₋₁₀alkynyl, C₁₋₁₀haloalkyl, C₁₋₁₀cyanoalkyl,C₁₋₁₀alkoxy, C₂₋₁₀alkenyloxy, C₂₋₁₀alkynyloxy, C₃₋₁₀cycloalkyl,heterocycloalkyl, aryl, heteroaryl, C₁₋₆alkylene-O—C₁₋₆alkyl,C₁₋₆alkylene-O—C₁₋₆haloalkyl, C₂₋₆alkenylene-O—C₁₋₆haloalkyl,C₂₋₆alkynylene-O—C₁₋₆haloalkyl, C₁₋₆alkylene-C₃₋₈cycloalkyl,C₁₋₆alkylene-heterocycloalkyl, C₁₋₆alkylene-aryl,C₁₋₆alkylene-heteroaryl, C(O)R⁷, OC(O)R⁷, C(O)OR⁷, C₁₋₆alkylene-O—R⁷,C₁₋₆alkylene-C(O)R⁷, C₁₋₆alkylene-O—C(O)R⁷, C₁₋₆alkylene-C(O)OR⁷,C₁₋₆alkylene-O—C(O)OR⁷, C₁₋₆alkylene-NR⁷R⁸, C₁₋₆alkylene-C(O)NR⁷R⁸,C₁₋₆alkylene-NR⁷C(O)R⁸, C₁₋₆alkylene-NR⁷C(O)NR⁷R⁸, C₁₋₆alkylene-S—R⁷,C₁₋₆alkylene-S(O)R⁷, C₁₋₆alkylene-SO₂R⁷, C₁₋₆alkylene-SO₂NR⁷R⁸,C₁₋₆alkylene-NR⁷SO₂R⁸, C₁₋₆alkylene-NR⁷SO₂NR⁷R⁸, C(O)NR⁷R⁸ andC₁₋₆alkylene-NR⁷C(O)OR⁸, wherein any cyclic moiety is optionallysubstituted with C₁₋₄alkyl and/or is optionally fused to a furthercyclic moiety; X is absent or is selected from the group consisting ofO, NH, NC₁₋₆alkyl, S, S(O), SO₂, C(O), C₁₋₆alkylene, C₂₋₆alkenylene,C₂₋₆alkynylene, C₁₋₆haloalkylene, C₃₋₈cycloalkylene,heterocycloalkylene, arylene and heteroarylene, or X is a combination oftwo or three of O, NH, NC₁₋₆alkyl, S, S(O), SO₂, C₁₋₆alkylene,C₂₋₆alkenylene, C₂₋₆alkynylene, C₁₋₆haloalkylene, C₃₋₈cycloalkylene,heterocycloalkylene, arylene or heteroarylene, bonded together in alinear fashion, provided that two or three of O, NH, NC₁₋₆alkyl, S, S(O)and SO₂ and not bonded directly to each other; R², R³ and R⁴ are eachindependently selected from the group consisting of C₁₋₁₀alkyl,C₂₋₁₀alkenyl, C₂₋₁₀alkynyl, C₁₋₁₀haloalkyl, C₁₋₁₀cyanoalkyl,C₁₋₁₀alkoxy, C₂₋₁₀alkenyloxy, C₂₋₁₀alkynyloxy, C₃₋₁₀cycloalkyl,heterocycloalkyl, aryl, heteroaryl, C₁₋₆alkylene-O—C₁₋₆alkyl,C₁₋₆alkylene-O—C₁₋₆haloalkyl, C₂₋₆alkenylene-O—C₁₋₆haloalkyl,C₂₋₆alkynylene-O—C₁₋₆haloalkyl, C₁₋₆alkylene-C₃₋₈cycloalkyl,C₁₋₆alkylene-heterocycloalkyl, C₁₋₆alkylene-aryl,C₁₋₆alkylene-heteroaryl, C(O)R⁷, OC(O)R⁷, C(O)OR⁷, C₁₋₆alkylene-O—R⁷,C₁₋₆alkylene-C(O)R⁷, C₁₋₆alkylene-O—C(O)R⁷, C₁₋₆alkylene-C(O)OR⁷,C₁₋₆alkylene-O—C(O)OR⁷, C₁₋₆alkylene-NR⁷R⁸, C₁₋₆alkylene-C(O)NR⁷R⁸,C₁₋₆alkylene-NR⁷C(O)R⁸, C₁₋₆alkylene-NR⁷C(O)NR⁷R⁸, C₁₋₆alkylene-S—R⁷,C₁₋₆alkylene-S(O)R⁷, C₁₋₆alkylene-SO₂R⁷, C₁₋₆alkylene-SO₂NR⁷R⁸,C₁₋₆alkylene-NR⁷SO₂R⁸, C₁₋₆alkylene-NR⁷SO₂NR⁷R⁸, C(O)NR⁷R⁸ andC₁₋₆alkylene-NR⁷C(O)OR⁸, wherein any cyclic moiety is optionally fusedto a further 5- to 7-membered cyclic moiety, wherein at least one of R²,R³ and R⁴ is C₁₋₆-alkylene-O—C₁₋₆haloalkyl, and wherein R², R³ and R⁴are optionally substituted with one or more independently-selected R⁶groups; R⁵ is selected from the group consisting of H, C₁₋₆alkyl,C₁₋₆haloalkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₃₋₈cycloalkyl,C₁₋₆alkylene-C₃₋₈cycloalkyl, aryl, heteroaryl, and heterocycloalkyl; R⁶is selected from the group consisting of C₁₋₆alkyl, OH, halo,O—(C₂₋₃alkylene)-O, C₁₋₆alkoxy, aryloxy, —NH—C₁₋₆alkyl, —N(C₁₋₆alkyl)₂,C₁₋₆alkylene-N(C₁₋₆alkyl)₂, C₁₋₆alkylene-NH—C₁₋₆alkyl, cycloalkyl,heterocycloalkyl, aryl and heteroaryl; and R⁷ and R⁸ are eachindependently selected from the group consisting of H, C₁₋₆alkyl,C₁₋₆haloalkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₃₋₁₀cycloalkyl,C₁₋₆alkylene-C₃₋₁₀cycloalkyl, heterocycloalkyl, aryl, C₁₋₆alkylene-aryl,C₁₋₆alkylene-heterocycloalkyl, heteroaryl, and C₁₋₆alkylene-heteroaryl,wherein any cyclic moiety is optionally fused to a further cyclicmoiety.
 2. The compound of claim 1 wherein R¹ is selected from: (i)C₁₋₆alkyl; (ii) a substituted or unsubstituted 5- or 6-memberedheteroaryl; and (iii) C₃₋₈heterocycloalkyl, wherein the substituents forthe 5- or 6-membered heteroaryl are independently selected fromC₁₋₄alkyl.
 3. The compound of claim 1, wherein R¹ is selected from: (i)substituted or unsubstituted thiazolyl; (ii) substituted orunsubstituted isothiazolyl; (iii) substituted or unsubstituted oxazolyl;(iv) substituted or unsubstituted isooxazolyl; (v) substituted orunsubstituted thiophenyl; (vi) substituted or unsubstituted furanyl;(vii) substituted or unsubstituted 1,2,4-triazolyl; (viii) substitutedor unsubstituted pyridyl; (ix) substituted or unsubstituted pyrazinyl;(x) substituted or unsubstituted pyrimidinyl; and (xi) substituted orunsubstituted 1,2,4-triazinyl, wherein the substituents for thiazolyl,isothiazolyl, oxazolyl, isooxazolyl, thiophenyl, furanyl,1,2,4-triazolyl, pyridyl, pyrazinyl, pyrimidinyl and 1,2,4-triazinyl areindependently selected from C₁₋₄alkyl.
 4. The compound of claim 3,wherein R¹ is selected from:


5. The compound of claim 2, wherein R¹ is C₃₋₈heterocycloalkyl and X isC₁₋₆alkylene.
 6. The compound of claim 5, wherein R¹ is selected frommorpholinyl, 1,4-oxazepanyl, thiomorpholinyl, 1,4-thiazepanyl,1,4-thiazepanyl-1-oxide, 1,4-thiazepanyl-1,1-dioxide,1,4-thiazinanyl-1-oxide, 1,4-thiazinanyl-1,1-dioxide, aziridinyl,azetidinyl, pyrrolidinyl, piperazinyl and 1,4-diazepanyl.
 7. Thecompound of claim 6, wherein X is —CH₂—.
 8. The compound of claim 1,wherein R² and R³ are each independently selected from the groupconsisting of C₁₋₁₀alkyl, C₂₋₁₀alkenyl, C₂₋₁₀alkynyl,C₁₋₆alkylene-O—C₁₋₆alkyl, C₁₋₆alkylene-O—C₁₋₆haloalkyl,C₂₋₆alkenylene-O—C₁₋₆haloalkyl and C₂₋₆alkynylene-O—C₁₋₆haloalkyl,wherein at least one of R² and R³ is C₁₋₆-alkylene-O—C₁₋₆haloalkyl. 9.The compound of claim 8, wherein R² and R³ are each independentlyselected from the group consisting of isobutyl, —CH₂—O—CH₃ and—CH₂—O—CHF₂, wherein at least one of R² and R³ is —CH₂—O—CHF₂.
 10. Thecompound of claim 8, wherein R⁴ is selected from the group consisting ofC₁₋₁₀alkyl, C₂₋₁₀alkenyl, C₂₋₁₀alkynyl, C₁₋₆alkyleneC₃₋₈cycloalkyl andC₁₋₆alkyleneC₆₋₁₄aryl.
 11. The compound of claim 1, wherein R⁵ isselected from the group consisting of H and C₁₋₆alkyl.
 12. The compoundof claim 1, wherein having the following relative stereochemistry:


13. The compound of claim 1, or a salt or solvate thereof, selectedfrom: 2-Methyl-thiazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;2-Methyl-thiazole-5-carboxylicacid-((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-methoxy-ethylcarbamoyl}-2-difluoromethoxyethyl)-amide;2-Methyl-thiazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-methoxyethyl)-amide;2-Methyl-oxazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;3-Methyl-isoxazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;Thiazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxoethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)amide;Oxazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;5-Methyl-thiophene-2-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;5-Methyl-furan-2-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;Thiophene-2-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;N-[(1S)-2-[[(1S)-2-[[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]amino]-1(difluoromethoxymethyl)-2-oxo-ethyl]amino]-1-(difluoromethoxymethyl)-2-oxo-ethyl]-1H-1,2,4-triazole-5-carboxamide;N-[(1S)-1-(difluoromethoxymethyl)-2-[[(1S)-1-(difluoromethoxymethyl)-2-[[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]-amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]-2-methyl-thiazole-5-carboxamide;Pyridine-2-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;N—((S)-1-{(S)-1-[(S)-1-Benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-nicotinamide;Pyridine-2-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;N-[(1S)-2-[[(1S)-2-[[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]amino]-1-(difluoromethoxymethyl)-2-oxo-ethyl]amino]-1-(difluoromethoxymethyl)-2-oxo-ethyl]-pyrimidine-2-carboxamide;[1,2,4]Triazine-3-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;Pyrimidine-4-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-difluoromethoxyethyl)-amide;2-Methyl-thiazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-3-methylbutylcarbamoyl}-2-difluoromethoxyethyl)-amide;2-Methyl-thiazole-5-carboxylic acid((S)-2-difluoromethoxy-1-{(S)-3-methyl-1-[(S)-3-methyl-1-((R)-2-methyloxiranecarbonyl)-butylcarbamoyl]-butylcarbamoyl}-ethyl)-amide,2-Methyl-thiazole-5-carboxylic acid((S)-1-{(S)-2-difluoromethoxy-1-[(S)-3-methyl-1-((R)-2-methyloxiranecarbonyl)-butylcarbamoyl]-ethylcarbamoyl}-3-methylbutyl)-amide;2-Methyl-thiazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-3-methylbutyl)-amide;2-Methyl-thiazole-5-carboxylic acid((S)-1-{(S)-2-difluoromethoxy-1-[(S)-3-methyl-1-((R)-2-methyloxiranecarbonyl)-butylcarbamoyl]-ethylcarbamoyl}-2-phenylethyl)-amide;2-Methyl-thiazole-5-carboxylic acid((S)-1-{(S)-1-[(S)-1-benzyl-2-((R)-2-methyl-oxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethylcarbamoyl}-2-phenylethyl)-amide;2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-N-[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]-3-phenylpropanamide;(S)—N—{(S)-1-[(S)-1-Benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethyl-carbamoyl]-2-difluoromethoxyethyl}-3-difluoromethoxy-2-(2-morpholin-4-yl-acetylamino)-propionamide;(2S)—N-[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-4-methylpentanamide;(2S)-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-4-methyl-N-[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]pentanamide;(2S)—N-[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]-2-[[(2S)-3-(difluoromethoxy)-2-[(2-morpholinoacetyl)amino]propanoyl]amino]-3-(1-methylcyclohexa-1,3,5-trien-1-yl)propanamide;(S)-4-Methyl-2-(2-morpholin-4-yl-acetylamino)-pentanoic acid{(S)-2-difluoromethoxy-1-[(S)-3-methyl-1-((R)-2-methyloxiranecarbonyl)-butylcarbamoyl]-ethyl}-amide;(S)-4-Methyl-2-(2-morpholin-4-yl-acetylamino)-pentanoic acid{(S)-1-[(S)-1-benzyl-2-((R)-2-methyloxiranyl)-2-oxo-ethylcarbamoyl]-2-difluoromethoxyethyl}-amide;(2S)—N-[(1S)-2-[[(1S)-1-benzyl-2-[(2R)-2-methyloxiran-2-yl]-2-oxo-ethyl]amino]-1(difluoromethoxymethyl)-2-oxo-ethyl]-2-[(2-morpholinoacetyl)amino]-3-phenylpropanamide;and(2S)-3-(difluoromethoxy)-N-[(1S)-1-(difluoromethoxymethyl)-2-[[(1S)-3-methyl-1-[(2R)-2-methyloxirane-2-carbonyl]butyl]amino]-2-oxo-ethyl]-2-[(2-morpholinoacetyl)amino]-propanamide.14. The compound of claim 13, wherein the compound is:

or a salt or solvate thereof.
 15. A pharmaceutical compositioncomprising a compound of claim 1 and a pharmaceutically acceptablecarrier.
 16. A method for inhibiting proteasome in a cell, comprisingadministering an effective amount of a compound according to claim 1 tothe cell.
 17. A method of inhibiting uncontrolled and/or abnormalcellular activities affected directly or indirectly by proteasomeinhibition in a cell, comprising administering an effective amount of acompound according to claim 1 to the cell.
 18. A method of treating adisease, disorder or condition that is mediated by proteasomeinhibition, comprising administering a therapeutically effective amountof a compound according to claim 1 to a subject in need thereof.
 19. Amethod of inhibiting the degradation of a protein by a proteasomecapable of degrading the protein, comprising contacting the proteasomewith an effective amount of a compound according to claim
 1. 20. Amethod of treating accelerated and/or enhanced proteolysis comprisingadministering a therapeutically effective amount of a compound accordingto claim 1 to a subject in need thereof.